Alternatives to OpenSMTPD
Compare OpenSMTPD alternatives for your business or organization using the curated list below. SourceForge ranks the best alternatives to OpenSMTPD in 2026. Compare features, ratings, user reviews, pricing, and more from OpenSMTPD competitors and alternatives in order to make an informed decision for your business.
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1
Greatmail
Greatmail
Dependable cloud based email hosting with spam filtering, antivirus protection, generous storage and webmail. Compatible with Outlook and all other POP3/IMAP clients. High volume SMTP service for responsible senders. Outbound relay service for transactional messages, email marketing campaigns, newsletters and other applications. Dedicated email servers, clustering and multiple IP load balancing for high volume senders. Fixed monthly cost with unlimited sending and reputation monitoring. Greatmail is an email service provider (ESP) specializing in business class email hosting, SMTP hosting and email servers. For ISPs, application programmers and cloud developers, we also provide custom solutions including dedicated IP servers and process specific, load balanced configurations with multiple servers. -
2
SMTP.com
Ziff Davis
Reliable SMTP relay and email delivery services. Powerful email delivery services that enable you to send and track high volume emails effortlessly. Integrate and start sending in minutes. All your transactional, email relay and email delivery needs under one roof. Whether you need a low-latency email delivery provider for your transactional emails, scalable infrastructure for high-volume sends or reliable backend solution for your marketing campaigns, SMTP is built to deliver. Reputation Defender is SMTP’s proprietary technology that uses big data to proactively monitor your email list health and safeguard your domain and IP reputation among ISPs by suppressing bad emails in your sends from hard and soft bounces. This ensures your delivery rates and inbox placement incrementally gets better over time.Starting Price: $25 per month -
3
Courier
Double Precision, Inc.
The Courier mail transfer agent (MTA) is an integrated mail/groupware server based on open commodity protocols, such as ESMTP, IMAP, POP3, LDAP, SSL, and HTTP. Courier provides ESMTP, IMAP, POP3, webmail, and mailing list services within a single, consistent, framework. Individual components can be enabled or disabled at will. The Courier mail server now implements basic web-based calendaring and scheduling services integrated in the webmail module. Advanced groupware calendaring services will follow soon. The Courier mail server's source code should compile on most POSIX-based operating systems based on Linux, and BSD-derived kernels. The Courier mail server should also compile on Solaris and AIX, with some help from Sun's or IBM's freeware add-on tools for their respective operating systems. The Courier mail server evolved out of several related projects, that merged together (more on that later). The Courier mail server implements SMTP extensions for mailing list management.Starting Price: Free -
4
Eudora Internet Mail Server
Eudora Internet Mail Server
Completely rewritten relay restrictions with an easier to use interface that gives finer control over relay security. New domain name resolver (DNR), EIMS now has it's own DNR, which works around bugs in the Open Transport DNR and performance problems with the OS X DNR. The new DNR does not currently support non-recursive DNSs. SMTP Submit port, this is a second SMTP port running on TCP port 587 by default. It currently works exactly the same as the standard SMTP port. This is handy for clients that are stuck behind an ISP that blocks port 25 access. Sending Setup option for maximum recipients per message. Expand SMTP Addresses option, you can now turn this off, with EIMS 3.1 and earlier it was always on. The SMTP server (both port 25 and 587) now reports Telnet connections and connections that look like port scans (connections where no data is sent and it doesn't time out).Starting Price: Free -
5
hMailServer
hMailServer
hMailServer is a free, open source, e-mail server for Microsoft Windows. It's used by Internet service providers, companies, governments, schools and enthusiasts in all parts of the world. It supports the common e-mail protocols (IMAP, SMTP and POP3) and can easily be integrated with many existing web mail systems. It has flexible score-based spam protection and can attach to your virus scanner to scan all incoming and outgoing email.Starting Price: Free -
6
Zentyal
Zentyal
Join Windows® clients to the domain and manage them transparently. No disruption to your users, no user or device CALs. Comes with industry-standard SMTP and POP3/IMAP mail server built upon the most established technologies and protocols. Guarantees reliable and secure Internet access and helps to manage all the basic network infrastructure services. Receive software updates until the EOL-date of each version and get support when needed. Zentyal offers an easy to use Windows Server® alternative. It comes with native compatibility with Microsoft Active Directory® allowing you to join Windows® clients to the domain and manage them easily, causing no disruption to your users. Zentyal includes the industry-standard SMTP and POP3/IMAP mail servers built upon the most established technologies and protocols. Gives you the opportunity to deploy Zentyal as a mail server, domain & directory server with mail or all-in one server.Starting Price: €195 per server -
7
Kingmailer
KingSMTP.com
KingSMTP.com (formerly known as Kingmailer.co, founded in 2017) is a Transactional SMTP service provider. It’s designed to help businesses reliably send emails such as order confirmations, password resets, or notifications, but it’s not intended for mass email campaigns or marketing.Starting Price: $0 per month -
8
MDaemon Email Server
MDaemon Technologies
The MDaemon Email Server was one of the first Microsoft Exchange alternatives offered to businesses around the world. It has been developed with the ongoing input from IT professionals seeking an easy-to-use, reliable, and secure mail server that does not require expensive administration or impose high per-user costs. It simplifies messaging and collaboration with a focus on security and privacy, an intuitive, user-friendly web mail design and by offering administrators Mobile Device Management, Business Instant Messaging, Document Sharing, and other enterprise-class features that can be managed with minimal support. MDaemon Email Server supports IMAP, SMTP, and POP3 protocols, and features include: integrated webmail with IM and document sharing, Outlook support, compromised password alerts, color-coded log files for quick and easy troubleshooting, customizable email policy setting to fit your unique network environment, Mobile Device Management, Account Hijack Detection, and more.Starting Price: $360 per year -
9
Mailu
Mailu
Mailu is a simple yet full-featured mail server as a set of Docker images. It is free software (both as in free beer & as in free speech), open to suggestions and external contributions. The project aims at providing people with an easily setup, easily maintained and full-featured mail server while not shipping proprietary software nor unrelated features often found in popular groupware. Main features include: Standard email server, IMAP and IMAP+, SMTP and Submission with autoconfiguration profiles for clients Advanced email features, aliases, domain aliases, custom routing Web access, multiple Webmails and administration interface User features, aliases, auto-reply, auto-forward, fetched accounts Admin features, global admins, announcements, per-domain delegation, quotas Security, enforced TLS, DANE, MTA-STS, Letsencrypt!, outgoing DKIM, anti-virus scanner, Snuffleupagus, block malicious attachments Antispam, auto-learn, greylisting, DMARC& SPF, anti-spoofingStarting Price: Free -
10
Horde
Horde
Horde is the most flexible groupware on the planet, and that makes it the perfect platform on which to build your business productivity software. Horde connects to (and officially supports) more backends (all the leading SQL, LDAP, IMAP, Sieve, SMTP, cache platforms available today) than any other open source groupware system. This means you can continue to use your existing userbase and your users do not have to remember any additional passwords. Horde's feature set rivals the largest enterprise email systems. We have an incredible feature set that compares favorably against any competition in our primary apps (mail, calendar, address book), and even more in our secondary apps (time tracking, wiki, ticketing, and more).Starting Price: Free -
11
MailEnable
MailEnable
MailEnable provides an end to end solution for providing secure email and collaboration services. A recent independent survey reports MailEnable as the most popular Windows Mail Server Platform in the world. Whether you are a hosting company providing email services to thousands of end users or a small business with a single domain, MailEnable provides a solution that will impress your mail users. MailEnable provides Windows Mail Server software with features comparable to Microsoft Exchange. It provides powerful messaging services like Exchange ActiveSync, IMAP, SMTP, POP3 and collaboration tools such as calendaring (CalDAV), contacts (CardDAV), tasks and notes.Starting Price: $349 -
12
iRedMail
iRedMail
The right way to build your mail server with open source softwares. Works on CentOS Stream, Rocky, Alma, Debian, Ubuntu, FreeBSD, OpenBSD. With iRedMail, you can deploy an OPEN SOURCE, FULLY FLEDGED, FULL-FEATURED mail server in several minutes, for free. We did the heavy lifting of putting all the open source components together and applying best practices. Our product does all the major tasks for you. Furthermore we offer professional support to back you up in case you have some problems. You have all personal data on your own hard disk, you can control the email security, inspect transaction log. No other organization can see the content of all messages. All components used in iRedMail are open source softwares, and you get the bug fixes and updates from the Linux/BSD venders you trust. iRedMail is the right way to build your mail server with open source softwares.Starting Price: Free -
13
Mail-in-a-Box
Mail-in-a-Box
Mail-in-a-Box lets you become your own mail service provider in a few easy steps. It’s sort of like making your own gmail, but one you control from top to bottom. Technically, Mail-in-a-Box turns a fresh cloud computer into a working mail server. But you don’t need to be a technology expert to set it up. Each Mail-in-a-Box provides webmail and an IMAP/SMTP server for use with mobile devices and desktop mail software. It also includes contacts and calendar synchronization. The box also includes other standard mail functionality like spam protection (spam filtering and greylisting), mail filter rules, email client autoconfiguration, and automated backups to Amazon S3 and other services. The box also includes automatic DNS configuration when you let it become your nameserver so that it can set important DNS records for mail deliverability and security including SPF, DKIM, DMARC, and MTA-STS. When enabled, DNSSEC (with DANE TLSA) provides a higher level of protection.Starting Price: Free -
14
SmarterMail
SmarterTools
SmarterMail is the ideal Microsoft Exchange alternative. It’s the only business email server on the market that offers native support for Exchange protocols: MAPI, EWS, and EAS, without requiring any additional software or plug-ins for Microsoft Outlook or other desktop or mobile clients. It delivers all the features of Exchange at a fraction of the cost. SmarterMail also includes audio/video group chat and Online Meetings for team collaboration at no extra charge. Its newest feature, the SmarterMail Marketplace, enables seamless integration with platforms like OnlyOffice, Collabora, and AI tools such as OpenAI’s ChatGPT. Available for both Windows and Linux, SmarterMail has lower hardware requirements, superior stability, and reduced maintenance costs. It’s the perfect solution for businesses of any size or industry seeking Exchange-level functionality, without the high costs.Starting Price: $500.00/one-time -
15
OpenSSH
OpenSSH
OpenSSH is the premier connectivity tool for remote login with the SSH protocol. It encrypts all traffic to eliminate eavesdropping, connection hijacking, and other attacks. In addition, OpenSSH provides a large suite of secure tunneling capabilities, several authentication methods, and sophisticated configuration options. Remote operations are done using ssh, scp, and sftp. Key management with ssh-add, ssh-keysign, ssh-keyscan, and ssh-keygen. The service side consists of sshd, sftp-server, and ssh-agent. OpenSSH is developed by a few developers of the OpenBSD project and made available under a BSD-style license. OpenSSH is incorporated into many commercial products, but very few of those companies assist OpenSSH with funding. Contributions towards OpenSSH can be sent to the OpenBSD Foundation. Since telnet and rlogin are insecure, all operating systems should ship with support for the SSH protocol included. The SSH protocol is available in two incompatible varieties, SSH 1 and SSH 2.Starting Price: Free -
16
Bit SMTP
Bit Apps
Many site owners face the spam mail problem for using the WordPress default PHP mail function. There may be some restrictions when it comes to mail service: sometimes emails are not delivered, sites cross the limit of outgoing mail. Bit SMTP plugin allows you to authenticate the mail service of your site by configuring the SMTP server of your desired mail service. SMTP is a protocol that helps your WordPress site make its email deliverability more easygoing & reliable. By enabling this feature, you can send mail from your site to your recipients via your preferred mail server. -
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SOGo
SOGo
SOGo is a fully supported and trusted groupware server with a focus on scalability and open standards. SOGo is released under the GNU GPL/LGPL v2 and above. SOGo provides a rich AJAX-based Web interface and supports multiple native clients through the use of standard protocols such as CalDAV, CardDAV and GroupDAV, as well as Microsoft ActiveSync. SOGo is the missing component of your infrastructure; it sits in the middle of your servers to offer your users a uniform and complete interface to access their information. It has been deployed in production environments where thousands of users are involved. -
18
SquirrelMail
SquirrelMail
SquirrelMail is a standards-based webmail package written in PHP. It includes built-in pure PHP support for the IMAP and SMTP protocols, and all pages render in pure HTML 4.0 (with no JavaScript required) for maximum compatibility across browsers. It has very few requirements and is very easy to configure and install. SquirrelMail has all the functionality you would want from an email client, including strong MIME support, address books, and folder manipulation. The need arose in our organization for the access of email and address books from anywhere in the world. Obviously a web interface is ideal for this, given that the user has access to the Internet. After reviewing several open source projects we realized that we were going to need to do some fairly major customizations to get things to be a nice fit for our needs. -
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Oracle Communications Messaging Server is a standards-based Internet messaging server designed for high-capacity, reliable message handling for service providers and their customers. Messaging Server provides support for several email protocols and can manage embedded text, sound, graphics, video files, and other files and formats.
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20
EmailLabs
Vercom
EmailLabs is part of the Vercom S.A Group, which implements technology solutions in the CPaaS model. We are a cloud SMTP server infrastructure: Cloud SMTP & Email API. With years of experience in sending to the most informed senders, we can make a measurable contribution to building email reputation and improving deliverability. We take care of standardization and security of both marketing, transactional and system messages of our customers. Thanks to the in-depth knowledge of our experts, we are able to prepare the infrastructure to ensure appropriate throughput and increase the sending speed for any market and any mailbox provider. Plug EmailLabs into your transactional sends - start sending in less than 5 minutes.Starting Price: Free -
21
WinGate
WinGate
WinGate Proxy Server is a highly capable HTTP Proxy server, SOCKS server, integrated Internet gateway and communications server designed to meet the access control, security and communications needs of today's businesses. In addition to a comprehensive range of features, WinGate Proxy Server's license options provide you the flexibility to match your needs to your budget, whether you need to manage an enterprise, small business, or home network. WinGate Proxy Server will share most types of Internet connection, allowing multiple users to simultaneously surf the web, retrieve their email, or use other internet programs, as if they were directly connected to the Internet. Whether it is a simple dialup modem or high speed fibre, WinGate Proxy Server can help to make the most out of the connection. WinGate Proxy Server supports a wide variety of Internet protocols, allowing applications such as Web browsers, messaging software, FTP and SSL.Starting Price: $109.95 one-time payment -
22
MailHog
MailHog
Inspired by MailCatcher, easier to install. MailHog is an email testing tool for developers: Configure your application to use MailHog for SMTP delivery. View messages in the web UI, or retrieve them with the JSON API. Optionally release messages to real SMTP servers for delivery. See MailHog libraries for a list of MailHog client libraries. ESMTP server implementing RFC5321. Support for SMTP AUTH (RFC4954) and PIPELINING (RFC2920). Web interface to view messages (plain text, HTML or source). Supports RFC2047 encoded headers. Real-time updates using EventSource. Release messages to real SMTP servers. Chaos Monkey for failure testing. See Introduction to Jim for more information. HTTP API to list, retrieve and delete messages. See APIv1 and APIv2 documentation for more information. HTTP basic authentication for MailHog UI and API. Multipart MIME support. Download individual MIME parts. In-memory message storage. MongoDB and file-based storage for message persistence. -
23
Microsoft SMTP Service
Microsoft
Microsoft SMTP Service is a mail server software that enables Microsoft Windows Server operating systems to send and receive emails. It is a component of Internet Information Services (IIS) and is used to relay emails between mail servers. Microsoft SMTP Service is a popular choice for organizations that need a reliable and scalable mail server solution. It is easy to install and configure and can be used with a variety of email clients. Microsoft SMTP Service supports a number of features, including: Relaying emails between mail servers: Microsoft SMTP Service can relay emails between mail servers, which means that it can be used to send and receive emails for multiple domains. Supporting multiple email clients: Microsoft SMTP Service can be used with a variety of email clients, including Microsoft Outlook, Mozilla Thunderbird, and Apple Mail. Providing security features: Microsoft SMTP Service provides a number of security features, such as authentication and encryption -
24
InterceptSuite
InterceptSuite
InterceptSuite is a comprehensive MITM proxy and TLS interception tool designed for security professionals, developers, system administrators, and network engineers. It features advanced SOCKS5 proxy capabilities with Python extension support, allowing users to write custom protocol dissectors and analysers for any TLS-encrypted protocol. The platform offers cross-platform compatibility across Windows, macOS, and Linux, with both free open-source and professional editions available. Key features include TLS packet interception, Universal TLS Upgrade Detection for protocols like SMTPS, IMAP, PostgreSQL TLS, and STARTTLS, plus PCAP file export for analysis with external tools like Wireshark.Starting Price: $10/month -
25
ClearOS
ClearCenter
Applications and an operating system come with your computer, tablet, and phone. So, why not on your server? HPE is redefining the small business server by offering ClearOS with HPE ProLiant servers. ClearOS is a simple, open, and affordable operating system with an intuitive graphical web-based user interface and an application marketplace with over 100 apps to choose from, with more being added every day. Leveraging open source software, you decide what applications you need and only pay for the applications and support you want. HPE and ClearCenter are making it easy for small, home, remote, and branch offices to have a server ready to use, out of the box, at no additional cost. HPE ProLiant integrated with ClearOS offers a simple, affordable, and secure experience. Building the IT solution that is just right for you has never been easier. -
26
SMTP Debug Tool
SMTP Debug Tool
Ensure flawless email communication with the SMTP Debug Tool, a completely free and secure way to diagnose SMTP connection issues. This tool connects to your SMTP server, initiates a test session, and provides a detailed log of the interaction between servers. Whether you're using popular email services like SendGrid, Google SMTP, Elastic Email, UniOne or Mailgun, this tool simplifies troubleshooting and helps resolve sending errors. With end-to-end encryption, your information remains private and secure. The tool doesn’t store any session logs or credentials, and you can further enhance security by changing your password after testing or using the optional “SMTP Blackhole” feature.Starting Price: $0 -
27
Citadel
Citadel
Email, collaboration, groupware, and content management - up and running in minutes, on your own hardware, or in the cloud. Citadel is easy, versatile, and powerful, thanks to its exclusive room-based architecture. No other platform seamlessly combines so many different features using this familiar and consistent metaphor. Citadel is 100% open source software using the GNU General Public License. It's not a crippled, cut-down version of some expensive "enterprise" edition. The software you download here is the very best available, and it's all free software.Starting Price: Free -
28
Cyrus IMAP
The Cyrus Team
Cyrus IMAP is an email, contacts and calendar server. Cyrus is free and open source. Features: Speed Security Efficiency Search CardDAV and CalDAV support Robust data storage Replication Scalable for large installations Flexible filtering support through Sieve Supports antivirus and antispam toolkits Handles deliverability: SPF, DKIM, DMARC Extensive authentication options, through Cyrus SASL JMAP support Long list of supported standardsStarting Price: Free -
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Instant Bulk SMTP
Instant Bulk SMTP
We understand how important role marketing plays in business and by looking that we have designed our Instant Bulk SMTP service which help to start sending your campaign in less than 30 minutes. Manage multiple contact lists, add, remove, delete, and import-export. Not only can you check bounces, opens, and click-throughs using our email analytics. You can set up or integrate with your applications. Easy to upgrade to a higher plan without any hassle. Instant Bulk SMTP is an outgoing email service that will allow you to send emails from your email address whether you have your own software or you don’t have your own software. We understand how important the role marketing plays in business and by looking at that we have designed our Instant Bulk SMTP service which helps to start sending your campaign instantly. Unlike typical email marketing services, our high-volume SMTP hosting service lets you send from your own application server, email client or a combination of different sources.Starting Price: $50 per month -
30
OpenText FirstClass
OpenText
The COVID-19 pandemic has changed the way we all live and work. The rise in remote working has resulted in a need for even greater communication, collaboration and flexibility. OpenText™ FirstClass® is a powerful collaboration solution that drives teamwork, improves communication, makes people and information easily accessible from any mobile device, and ensures team members are connected within the organization. FirstClass is a fully integrated solution that is cost-effective, flexible and easy to administer. It empowers individuals and teams to work together toward a common goal, with a shared sense of purpose and new ways to participate. Designed to support collaboration, FirstClass offers easy and secure communication, mobile access, personalization, integration with other applications, and safe, reliable archiving. -
31
SyncBackPro
2BrightSparks
SyncBackPro is an advanced file backup and synchronization program that can be used with hard drives, removable media (e.g. USB drives), FTP, FTPS, and SFTP servers, Zip64 archives (with 256-bit AES encryption), POP3/IMAP4/SMTP email servers, Media Transfer Protocol devices, network shares, and cloud storage services (S3, Azure, Dropbox, OneDrive, Google Drive, Box, and many others). Highly configurable, SyncBackPro includes: open/locked file copying; file versioning; scripting; fast backup; true synchronization; Zip64 support; compression filtering; detailed and easy to read log files; email results; simulated backups and restore; file filters; sub-directory selection; copy verification; background backups; auto-close of programs; profile groups; compare files, and an extensive context sensitive help file.Starting Price: $54.95/one-time/user -
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PriMailer
Dunes Factory
Use the full power of all your SMTPs without the hassle of multiple logins. Integrate your SMTPs and let Primailer do the rest. We cater to all our clients. In need of a limited credit-based plan or want to integrate your own SMTP to our unlimited email plan. Integrate Primailer Validator, Kickbox, Zerobounce, Thechecke, Everifier, and many more email validator services in just 2 clicks. Create your email campaign in just 4 Steps. Setup open tracking, URL tracking, and advance reoccurring on the go. Create an email autoresponder campaign based on your subscribers’ actions (campaign open/campaign sent/user subscriber). Take actions based on duplicate, distinct or missing subscribers between two lists. Easily split your subscribers of a list into multiple sublists with a single click. Sending transactional emails shouldn’t be hard with the right transaction email service. With Primailer transactional email service provider you can easily send and track emails. -
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KumoMTA
Kumo Corp
KumoMTA is an Open-Source, enterprise-grade email message transfer agent (MTA) software for sending high-volume, business-critical emails. KumoMTA is typically chosen by high-volume email users looking to replace PowerMTA, Momentum, or traditional Open Source MTAs. KumoMTA offers high-performance message relay to the tune of millions of messages per hour per server, combined with extreme flexibility and configurability through its use of a Lua scripting engine for configuration and message management. For more information on KumoMTA see our Sourceforge project page.Starting Price: $0 -
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mailcow
mailcow
mailcow: dockerized is an open source groupware/email suite based on Docker. mailcow relies on many well known and long used components, which in combination result in an all around carefree email server. Each container represents a single application, connected in a bridged network.Starting Price: Free -
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Hexamail POP3 Downloader
Hexamail
POP3 Downloader is a high-performance, scalable, real-time POP3 connector for your mail server. It supports downloading and forwarding any POP3 or IMAP account email to any email server that supports SMTP or IMAP. Key Features: 100% Compatibility with all versions of Exchange 100% Compatibility with all SMTP servers End-user management via a web interface Antivirus and Antispam options IMAP Support (with folders) IMAP Push Support Gmail Support 1-minute scheduling No email size limits Microsoft Exchange integration without the need for a public SMTP server or static IP address Migrate or integrate unlimited external POP3 or IMAP email accounts into local mailboxes Continue receiving mail from legacy accounts during migration to a new mail server IMAP migration or IMAP sync between two IMAP servers Reliable, easy to install, and cost-effective solution Streamline your email integration processes and automate email downloads with Hexamail POP3 Downloader.Starting Price: $114/10 users -
36
Bancor
Bancor
Bancor is a protocol for the creation of Smart Tokens, a new standard for cryptocurrencies convertible directly through their smart contracts. Bancor is an on-chain liquidity protocol that enables automated, decentralized exchange on Ethereum & across blockchains. The Bancor Protocol is a fully on-chain liquidity protocol that can be implemented on any smart contract-enabled blockchain. The Bancor Protocol is an open-source standard for liquidity pools, which in turn provide an endpoint for automated market-making (buying / selling tokens) against a smart contract. Bancor Network currently operates on the Ethereum and EOS blockchains, but the protocol is designed to be interoperable for additional blockchains. Our implementation can be easily integrated into any application enabling value exchanges. Our implementation is open source and permissionless, and ecosystem participants are encouraged to contribute to and enhance the Bancor Protocol. -
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Halon
Halon
Halon MTA makes you more competitive, by secure and timely delivery of important emails and rapid feature implementation. At the same time, you will cut your development and maintenance costs by half. The Halon MTA is a flexible email operation and security platform. It enables organizations that operate large-scale email services to offer competitive features by rapid implementation and to lower maintenance costs through reliable deployment and reduced complexity. Halon MTA consolidates your email infrastructure, reducing risk and complexity. It makes email infrastructure scalable, simple to manage, rich in functionality and easy to evolve. Suffering from slow and costly implementation of email features and new standards, leading to poor end customer experience? Halon increases email service competitiveness by enabling rapid implementation and reliable deployment. In contrast to traditional layered email infrastructure, Halon's holistic approach cuts system complexity. -
38
Artica Proxy
Artica Tech
Artica project began in 2004 and stemmed from ideas about how to improve the Open Source security solutions available at the time, which were difficult and often expensive to implement and maintain. Artica provides a Powerful user-friendly Web interface and it’s designed to allow every IT administrator, with or without Linux knowledges, to install and maintain network service, like Proxy service, Reverse-Proxy service, DNS service, DNS Filter service, Firewall service, IDS service, SMTP service and more. Today, with around 110.000 servers installed worldwide, Artica solutions are used from small to large enterprises and in Public Government ServicesStarting Price: €100 -
39
turboSMTP
turboSMTP
TurboSMTP understands that email is not just a means of communication but the backbone of your customer engagement strategy. TurboSMTP Email API is trusted by developers and marketers alike for its time-saving features, scalability, and delivery expertise. Our service offers a flexible SMTP relay solution along with advanced features tailored to meet the needs of businesses of all sizes. With our intuitive dashboard, powerful features, and dedicated support, ensuring the delivery of your emails is seamless and uninterrupted. TurboSMTP's infrastructure is built to scale, whether you're sending a few hundred emails or millions. Integration with our service is effortless, with sample code libraries available in multiple languages, interactive documentation, and customizable templates. Monitor engagement data and optimize deliverability with our comprehensive reporting tools. Trust TurboSMTP to deliver your emails reliably and efficiently, empowering you to engage with your audience.Starting Price: $14.95 per month -
40
Server Check
FearWorks Media Ltd.
The Server Check Monitoring System continually monitors your websites and other internet-based services (Ping, SMTP, IMAP, FTP, etc.) and makes sure you're the first to know when there's an outage. Don't lose any more visitors to downtime. Our FREE 10-monitor version of Server Check lets you get started with monitoring in less than five minutes completely free! Get alerted as soon as something stops working: visual alerts, audible alarms, emails and SMS texts to as many admins as you need. Server Check makes sure you know about it so you can fix it! Quick setup of all common protocols, including HTTP & HTTPS, Ping, FTP, SMTP, POP3, IMAP, TCP, MySQL. Monitor them all and stay ahead of any long outages that might lose customers! View statistics for each monitor, response time graphs, outage length reports, web-based stats and uptime pages, and keep track of uptime and downtime over the last 12 months.Starting Price: Free -
41
SMTP2GO
SMTP2GO
Send and track all emails easily and securely with SMTP2GO, a reliable outgoing email service solution. SMTP2GO features a redundant, multi data center infrastructure that allows users to send emails even if there is a major internet outage. SMTP2GO has features like real-time analytics, bounce/spam tracking, weekly summaries, spamtrap detection, blacklist monitoring, DKIM/SPF, and more.Starting Price: $10 per month -
42
Labnify
Labnify
Labnify provisions email API and SMTP-integrated mailer so you won't need any of those pesky SMTP credentials. A system that delivers and track mass emails reliably enriched with features like real-time analytics, open/click metrics, bounce/spam tracking, template builder, and more. No one likes being blacklisted. That's why our innovative blacklist monitoring feature keeps a watchful eye on your sending reputation, ensuring your emails always land in the recipient's inbox. Plus, Labnify takes email authentication seriously, utilizing DKIM/SPF authentication to enhance your deliverability and add that extra layer of security. Millions of emails have relayed via Labnify as it's easy to work with. Simply import your email list and hit SEND without the need for an SMTP credential, making it a 2-in-1 email marketing stack. Built on the most cost-effective Email API, deliverability and scalability matter. Easily connect and send your email using our automated system and scale.Starting Price: $99/month -
43
NethServer
NethServer
Analyzes all web traffic and blocks selected websites via HTTP and even HTTPS using Squid proxy. Integrated with ClamAV antivirus and site blacklists. Multi-domain web server with ready LAMP stack. Virtual hosting allows to host multiple domain names on a single server. Based on NextCloud provides universal access to your files via the web, your computer or your mobile devices, wherever you are. Provide a private Slack-alternative with Mattermost. Open source messaging platform that enables secure team collaboration. Modern and powerful web interface based on Cockpit that simplifies common administration tasks, very easy and fast installation. Based on CentOS/RHEL, a widespread and popular server distribution, trusted by routine security updates, and rock solid stability.Starting Price: €48 per year -
44
OpenBSD
OpenBSD
OpenBSD is developed entirely by volunteers. The project's development environment and developer events are funded through contributions collected by The OpenBSD Foundation. Contributions ensure that OpenBSD will remain a vibrant and free operating system. Hence the OpenBSD project has embedded cryptography into numerous places in the operating system. We require that the cryptographic software we use be freely available and with good licenses. We do not directly use cryptography with nasty patents. We also require that such software is from countries with useful export licenses because we do not wish to break the laws of any country. Be as politics-free as possible; solutions should be decided on the basis of technical merit.Starting Price: Free -
45
Spam Arrest
Spam Arrest
Before using Spam Arrest, over 90% of our customers tried a spam filter on their inbox, yet spam still got through. Spam Arrest protects your mailbox from 100% of spam with a patented method for verifying relationships between you and your valued contacts, making email safe for everyone. Access your email using your favorite POP3/IMAP-compatible program (such as Outlook or Eudora), or from anywhere using our powerful webmail system. Get a new email address, as well as protect your existing mailboxes. Patented challenge, response technology blocks 100% of automated spam. Webmail allows you to access your email from any web browser, without having to install any additional software. SMTP is a standard protocol used for sending email. When you send email through the Spam Arrest SMTP server or webmail, the person you are sending email to is automatically added to your whitelist, so that they can reply to you without having to complete the verification process. -
46
Kolab Now
Apheleia IT AG
Secure and private email, calendars and more. 100% Free & Open Source Software (FOSS). Open standards and formats used for all storage and communication. No vendor lock-in. All data stored under Swiss jurisdiction. User data never transmitted to any third party without explicit consent. GDPR, HIPAA and PCI compliant. Built secure from the ground up. Supports perfect forward secrecy (PFS). End-to-end encryption available. No back doors. Our documentation contains answers to most frequently asked questions and much more. Are you looking for an instant answer to your question or a quick solution for your problem, our Knowledgebase is where you will likely find it. If you can’t find the answer in our documentation, you can always contact support.Starting Price: $9.90 per month -
47
Kopano
Kopano
We provide you with your digitally sovereign solution to keep track of your e-mails and calendars, to organize yourself with tasks or to stay in contact with team colleagues via video meeting. Kopano Groupware is an e-mail and calendaring solution, which can be operated digitally sovereign. Its functionality is comparable to that of Microsoft Outlook and Exchange. Kopano Groupware installations can be operated with more than 100,000 users. Kopano Groupware is an e-mail and calendar server that provides users with their daily communication and organizational data on all devices and connects teams. Data can be jointly edited in public folders or shared with others from your own inbox.Starting Price: $17 per year -
48
Daily Sender
Daily Sender
Send emails to unlimited email subscribers with just one click. With online email marketing software its easy to setup html/text campaigns, send and track. You can now track opened, unsubscribes and bounces. Software also have auto bounce processing and one click unsubscribe features. We also offer Dedicated Bulk Smtp Servers if you want to send emails with your own dedicated IPs then please click here to see our dedicated smtp server plans. Daily Sender provides a complete email marketing solution which gives our client a platform to enhance their product and grow their business. Our clients are located worldwide and use our services to send email marketing campaigns. We provide reliable delivery, scalability and real-time analytics. You are also provided with a platform where-in you can track your complete statistics. Our web-based tools help businesses grow by staying in touch with customers and prospects through email.Starting Price: $149.99 -
49
CommuniGate Pro
CommuniGate Software
Our end to end Unified Communications technology begins with the platform CommuniGate Pro. The system enables large scale Unified Communications with open API’s for integration into business applications. CommuniGate Pro scales dynamically to 100’s of millions of accounts. Ideally suitable for “Nation” scale alert systems, multimodal communications within web applications, or compartmentalized high-security network topologies. However, big scale does not mean trade-offs on efficiency or reliability. The platform is extremely agile for resilient applications in military or embedded environments. CommuniGate Pro is approved for governmental agency use in Europe and in the USA. Military, transportation and research center use is legendary for mind bending stability with uptimes like VMS. CommuniGate Pro enables banks to deploy mail to millions of clients for online self care while respecting compliance regulations. The signaling features of the server can be deployed in a hybrid system. -
50
WP Mail SMTP
WP Mail SMTP
If you're having issues with WordPress not sending emails, you're not alone. With the rise of aggressive spam filtering, it's tough to reach the inbox unless your emails are configured correctly. Once you've switched from the default WordPress email settings over to WP Mail SMTP, your email deliverability issues will be solved for good. Are you missing out on leads and sales because emails sent from your WordPress site are ending up in the spam folder? Missing out on these opportunities can be a big hit to your bottom line. When your emails are properly authenticated using SMTP, they'll be recognized as legitimate and bypass those aggressive spam filters. WP Mail SMTP integrates with all of the best secure SMTP providers. No matter how many emails you need to send, you can connect with the right provider for your business needs and budget.Starting Price: $49 per year
