Open Source Windows Communications Software

Communications Software for Windows

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Browse free open source Communications software and projects for Windows below. Use the toggles on the left to filter open source Communications software by OS, license, language, programming language, and project status.

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  • 1
    qBittorrent

    qBittorrent

    A free and reliable P2P BitTorrent client

    An advanced and multi-platform BitTorrent client with a nice Qt user interface as well as a Web UI for remote control and an integrated search engine. qBittorrent aims to meet the needs of most users while using as little CPU and memory as possible.
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    Downloads: 957,036 This Week
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  • 2
    WinSCP

    WinSCP

    WinSCP is a free SFTP, SCP, S3, WebDAV, and FTP client for Windows.

    WinSCP is a popular free file manager for Windows supporting SFTP, FTP, FTPS, SCP, S3, WebDAV and local-to-local file transfers. A powerful tool to enhance your productivity with a user-friendly interface and automation options like .NET assembly or batch file scripting. Use WinSCP also for file editing, directory synchronization and site management. WinSCP is open-source and well documented. It is available in English and many other languages.
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    Downloads: 259,805 This Week
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  • 3
    Scrollout F1

    Scrollout F1

    An easy-to-use anti-spam email gateway

    • Designed for Linux and Windows email system administrators, Scrollout F1 is an easy to use, already adjusted email firewall (gateway) offering free anti-spam and anti-virus protection aiming to secure existing email servers, old or new, such as Microsoft Exchange, Lotus Domino, Postfix, Exim, Sendmail, Qmail and others. • Built-in multilayer security levels make configuration effort equal to a car radio. • It combines simplicity with effective protection using powerful open source with additional set of rules & filters. • Available as 64bit: - ISO image (Internet connection required during installation) - install from scratch (Internet connection required during installation). • Minimum Requirements (for 5,000 messages/day): 1 GB of RAM 30 GB storage drive 1 Processor x86/AMD64 1 Ethernet x 1 IPv4 address UDP ports: 53 123 4500 6277 24441 TCP ports: 25 80 443 2703
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    Downloads: 97,128 This Week
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  • 4
    Anti-Spam SMTP Proxy Server

    Anti-Spam SMTP Proxy Server

    Anti-Spam SMTP Proxy Server implements multiple spam filters

    The Anti-Spam SMTP Proxy (ASSP) Server project aims to create an open source platform-independent SMTP Proxy server which implements auto-whitelists, self learning Hidden-Markov-Model and/or Bayesian, Greylisting, DNSBL, DNSWL, URIBL, SPF, SRS, Backscatter, Virus scanning, attachment blocking, Senderbase and multiple other filter methods. Click 'Files' to download the professional version 2.8.1 build 24261. A linux(ubuntu 20.04 LTS) and a freeBSD 12.2 based ready to run OVA of ASSP V2 are also available for download. NOTICE: V1 development has been stopped at the end of 2014 (1.10.1 build 16060). Possibly there will be done some bugfixing in future. Please upgrade to V2, which is and will be actively maintained.
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    Downloads: 38,714 This Week
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    eMule

    A free peer-to-peer (P2P) file sharing client

    eMule is a free peer-to-peer (P2P) file-sharing client for Microsoft Windows that was launched in 2002 as an alternative to eDonkey2000. To date, eMule is one of the world’s largest and most trustworthy P2P file-sharing clients. eMule includes advanced search features, file checks for corruptions while downloading, a preview while downloading function, and a credit system to reward frequent uploads.
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    Downloads: 11,172 This Week
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  • 6
    WSJT

    WSJT

    Weak signal ham radio communication

    The WSJT project implements software for amateur radio communication using state-of-the-art digital techniques. Typical applications involve "DXing" at LF, MF, HF, and VHF+ frequencies, including meteor scatter and EME ("moonbounce"). Major emphasis is placed on weak-signal techniques. Summary Program Descriptions: WSJT-X supports the communication protocols FST4, FT4, FT8, JT4, JT9, JT65, Q65, MSK144, WSPR, FST4W, and Echo, each optimized for different sorts of radio-wave propagation. MAP65 and QMAP are designed for EME at VHF and higher frequencies. MAP65 provides a panoramic, polarization-matching receiver for the Q65 and JT65. modes. QMAP works together with WSJT-X to provide a panoramic receiver for Q65 modes covering a 90 kHz sub-band. Programs WSJT and WSPR are interesting primarily for historical reasons. They are superseded by WSJT-X.
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    Downloads: 7,460 This Week
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  • 7
    FileZilla®

    FileZilla®

    A fast cross-platform FTP client

    FileZilla® is a cross-platform FTP, SFTP, and FTPS client with a vast list of features, which supports Windows, Mac OS X, Linux, and more. FileZilla's dynamic tools help you move files between your local machine and your Web site's server effortlessly. For example, Filezilla lets you compare your files with in-directory server files to manage file syncing. You can also tab browse between servers and transfer files to them simultaneously, as well as edit server files on the go. And Filezilla is available in 47 languages worldwide!
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    Downloads: 6,839 This Week
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  • 8
    WSJT-X Improved
    WSJT-X_IMPROVED is published by Uwe Risse, DG2YCB. It is an enhanced edition of the excellent WSJT-X software by Joe Taylor K1JT, Steve Franke K9AN, Bill Somerville G4WJS, myself and others (https://sourceforge.net/projects/wsjt/) that provides several additional features and improvements, as well as more frequent updates and bug fixes. Notes: wsjt-x_improved is experimental and is licensed under GNU GPL v3 (https://www.gnu.org/licenses/gpl-3.0.txt). I am not aware of any adverse effects. However, use it at your own risk! Subscribe to the mailing list: https://sourceforge.net/projects/wsjt-x-improved/lists/wsjt-x-improved-community. Find the various installation packages on the "Files" tab (https://sourceforge.net/projects/wsjt-x-improved/files/).
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    Downloads: 5,510 This Week
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  • 9
    Snap7

    Snap7

    32/64 bit multi-platform Ethernet S7 PLC communication suite

    Snap7, through three specialized components: Client and the inedited Server and Partner, allows you to definitively integrate your PC based systems into a PLC automation chain. Designed to transfer large amounts of hi-speed data in industrial facilities, it scales easily, down to small Linux Arm boards such as Raspberry PI. Hi level object oriented wrappers are provided, currently C/C++, .NET/Mono, Pascal, LabVIEW, Python with many source code examples. Very easy to use, a full working server example is not bigger than the “Hello world”. Many projects/makefiles are ready to run to easily rebuild Snap7 in any platform without the need of be a C++ guru. Very detailed documentation provided.
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    Downloads: 5,360 This Week
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  • 10
    Zero Install
    Zero Install is a decentralised cross-distribution software installation system. Create one package that works everywhere! With dependency handling and automatic updates, full support for shared libraries, and integration with native package managers
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    Downloads: 2,986 This Week
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  • 11
    Matroska is an open standard audio/video container format. Visit our homepage at http://www.matroska.org
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    Downloads: 2,953 This Week
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  • 12
    RealTerm: Serial/TCP Terminal

    RealTerm: Serial/TCP Terminal

    Serial and TCP terminal for engineering and debugging

    Serial terminal program for engineering. Ideal for development, reverse engineering, debugging, datalogging and capture, and automatic test. The website is a comprehensive manual for Realterm. It has an comprehensive ActiveX/COM automation support so it can be used a serial component by other programs. An extensive commandline interface supports batch files and simple automatic test programming. Commands can be sent to running instances, and commands can be stored and run in files. [ActiveX](http://realterm.sourceforge.net/index.html#ActiveX_Interface) and [Command Line](http://realterm.sourceforge.net/index.html#Command_Line_Parameters) commands are well documented. Sourceforge major releases are only made occasionally. To follow development versions see News and subscribe.
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    Downloads: 2,821 This Week
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  • 13
    Telegram Desktop

    Telegram Desktop

    Telegram Desktop messaging app

    Telegram Desktop is the official C++/Qt-based cross-platform client for Telegram, implementing the full Telegram API and MTProto protocol for secure messaging, voice/video calls, file sharing, and chat features. It provides message sync across devices, supports themes, stickers, bots, and is actively maintained.
    Downloads: 541 This Week
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  • 14
    IssabelPBX

    IssabelPBX

    Issabel PBX - Unified Communications

    Open Source and Unified Communications partners created a new platform based on an Elastix® fork (currently purchased by 3CX) to provide the community with continuity, peace of mind and support needed to continue with their PBX and operation developments. Contribute to the funding of Issabel on https://www.patreon.com/issabel
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    Downloads: 2,575 This Week
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  • 15
    The portable Universal Plug and Play (UPnP) SDK provides support for building UPnP-compliant control points, devices, and bridges on several operating systems. The main repository is at GitHub in https://github.com/pupnp/pupnp. This is just a clone repository for legacy reasons. Old SourceForge repo: git://pupnp.git.sourceforge.net/gitroot/pupnp/pupnp
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    Downloads: 3,485 This Week
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  • 16

    QModMaster

    Modbus TCP,RTU Master Software.

    QModMaster is a free Qt-based implementation of a ModBus master application. A graphical user interface allows easy communication with ModBus RTU and TCP slaves. QModMaster also includes a bus monitor for examining all traffic on the bus. QModMaster is based on libmodbus <http://www.libmodbus.org/> for modbus communication and on QsLog <https://bitbucket.org/codeimproved/qslog> for logging. Supports both Windows and Linux. For Windows a pre-compiled binary is availiable. It does not require instalation, just unzip and run. You can download the latest stable version from here <https://sourceforge.net/projects/qmodmaster/files/qModMaster-Win32-exe-0.5.2-3.zip/download>. Source code is availiable for Windows and Linux for compilation using Qt <http://www.qt.io/download>. Check out my modbus slave project <http://sourceforge.net/projects/pymodslave/>. Checkout the following youtube videos : <https://www.youtube.com/channel/UC3Tk2gE-KGtwOq8WWmb2R7g>
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    Downloads: 2,104 This Week
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  • 17
    BeeBEEP (Free Office Messenger)

    BeeBEEP (Free Office Messenger)

    You can message and share files inside your intranet without a server.

    BeeBEEP is a secure (encryption based on Rijndael Algorithm, AES) peer to peer office messenger. You can talk and send files with all your colleagues inside a local area network such of an office, home or internet cafe without a server. BeeBEEP works also with VPNs. This serverless application is indispensable in all those places where privacy and security an essential requirement. For more info visit: https://www.beebeep.net
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    Downloads: 1,896 This Week
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  • 18
    Vuze - Azureus

    Vuze - Azureus

    An extremely powerful and configurable BitTorrent client

    Vuze (formerly Azureus) is an extremely powerful and configurable BitTorrent client. Search and download torrent files. Play, convert and transcode videos and music for playing on many devices such as PSP, TiVo, XBox, PS3, iTunes (iPhone, iPod, Apple TV).
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    Downloads: 2,192 This Week
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  • 19
    Pidgin IM

    Pidgin IM

    A universal instant messaging (IM) program

    See https://pidgin.im/about/ for more information. Pidgin is an instant messaging program which lets you log in to accounts on multiple chat networks simultaneously. It runs on Windows, Linux, and other UNIX operating systems. Pidgin is compatible with the following chat networks out of the box: AIM, ICQ, Google Talk, Jabber/XMPP, MSN Messenger, Yahoo!, Bonjour, Gadu-Gadu, IRC, MXit, Novell GroupWise Messenger, Lotus Sametime, SILC, SIMPLE, MySpaceIM, and Zephyr. It is written in C and makes heavy use of GLib and GTK+. Finch is a command line instant messaging program. It also lets you log in to accounts on multiple chat network simultaneously, and it is compatible with the same chat networks as Pidgin. It is written in C and makes heavy use of GLib and ncurses.
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    Downloads: 9,334 This Week
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  • 20
    fldigi

    fldigi

    Ham Radio Digital Modem Application

    Fldigi is a modem program for most of the digital modes used by radio amateurs today: CW, PSK, MFSK, RTTY, Hell, DominoEX, Olivia, and Throb are all supported. It can help calibrate a sound card to a time signal and do frequency measurement tests. NOTICE: You must proceed to the Files section to locate the correct fldigi, flrig etal download for your particular operating system. Do not blithely use the big green Download button! Use the "Files" menu item or the "Browse All Files" link.
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    Downloads: 2,114 This Week
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  • 21
    aMule stands for all-platform eMule file-sharing program. It is affiliated with the eMule project and was forked from xMule on 08/2003. It connects to the eDonkey2000 network, supports Linux, Mac, Solaris, *BSD platforms, and nearly every processor arch. For development, feature requests, issues and bug reporting, go to the GitHub project page at https://github.com/amule-project/amule .
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    Downloads: 1,552 This Week
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  • 22
    Shareaza

    Shareaza

    A universal P2P file sharing client for Windows

    Shareaza is a very powerful multi-network peer-to-peer file-sharing client supporting Gnutella² G2, Gnutella, eDonkey2000 / eMule, DC++, HTTP, FTP and BitTorrent / DHT protocols for Windows or Wine.
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    Downloads: 1,302 This Week
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  • 23
    RATS Search

    RATS Search

    BitTorrent P2P multi-platform search engine for Desktop

    Rats Search is a cross-platform search tool for torrent indexing across multiple BitTorrent DHT networks. It provides a GUI for searching decentralized torrent metadata in real time without relying on centralized indexes. Built with Electron and Vue.js, Rats Search emphasizes decentralization and anonymity, allowing users to explore content from distributed sources such as the BitTorrent Mainline DHT and WebTorrent. It supports filtering, magnet link generation, and acts as a privacy-conscious alternative to torrent search engines.
    Downloads: 288 This Week
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  • 24
    LocalSend

    LocalSend

    An open-source cross-platform alternative to AirDrop

    LocalSend is a free, open-source app that allows you to securely share files and messages with nearby devices over your local network without needing an internet connection. LocalSend is a cross-platform app that enables secure communication between devices using a REST API and HTTPS encryption. Unlike other messaging apps that rely on external servers, LocalSend doesn't require an internet connection or third-party servers, making it a fast and reliable solution for local communication.
    Downloads: 282 This Week
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  • 25
    dcm4che is an implementation of DICOM and IHE actors in Java. Homepage: http://www.dcm4che.org, Google Group: http://groups.google.com/group/dcm4che?hl=en, Wiki: http://www.dcm4che.org/confluence, Issue Tracking: http://www.dcm4che.org/jira
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    Downloads: 1,358 This Week
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