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).
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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.
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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.
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Aid4Mail
Aid4Mail is a fast, reliable, and highly accurate tool to collect, recover, search, and convert emails. It supports most mailbox file formats (e.g. PST, OST, OLM, mbox), IMAP accounts (e.g. Yahoo! Mail, AOL) and popular mail service providers (e.g. Microsoft 365, Exchange, Gmail). Aid4Mail can recover double-deleted messages and corrupted emails, and extract MIME data from certain types of unknown file formats through file carving.
Aid4Mail provides a large array of tools to search and filter out unwanted emails during conversion. Save time by using native pre-acquisition filters to download a subset of your mail from Exchange, Office 365, Gmail and other webmail services. Use Aid4Mail’s integrated search engine to cull-down your email collection. Its search operators are very similar to Gmail and Office 365.
Aid4Mail is used by Fortune 500 companies, government agencies and legal professionals around the world. It is made in Switzerland by perfectionists.
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