LibreOffice

Free and Open Source alternative to the Microsoft Office Suite. Has alternatives to Word, Powerpoint and Excel, for instance LibreOffice can open and save to Microsoft file formats, OpenDocument, and many others.
https://www.libreoffice.org/

Scribus

Printer quality publishing application. Create signs, brochures, and newsletters.
http://www.scribus.net/

 

 

Firefox

Better browser. This browser is more secure than IE and allows you to use tabs to view multiple pages. 
https://www.mozilla.org/firefox

 

 

Thunderbird

Thunderbird is a mail and news reader with much of the same functionality that Outlook has. 
https://www.thunderbird.net

CD Burner XP Pro

Not open source, but still a great CD burner. It will burn several types of CDs and DVDs. It will also burn a CD from an ISO. 
http://www.cdburnerxp.se/

 

Audacity

The premier audio editing tool. This program allows you to record, modify and mix audio for a variety of projects. It is used to build podcasts and create full-length CDs.
http://audacity.sourceforge.net/

GIMP

Comparable to Adobe Photoshop features, GIMP is an image editing program
http://www.gimp.org/

CDex

Rip CD Audio into WAV files. You can also compress the files using add-in programs to convert the files to mp3.
https://cdex.mu/

MythTV

Create a PVR so that you can record live TV and store your DVD collection for easy playback.
http://www.mythtv.org/

Windows Defender

The built in Antivirus for Microsoft Windows, comes already installed and works out of the box.

https://www.microsoft.com/en-us/windows/comprehensive-security

MalwareBytes

When Windows Defender doesn't offer enough protection MalwareBytes is the perfect complement.

https://www.malwarebytes.com/

 

 

A list of Open Source Free Tools for Windows

Audio editing tools

  • CDex [GNU GPL]
  • Ogg Vorbis
  • Musepack [GNU LGPL, BSD]
  • Audacity [GNU GPL]
  • LAME [GNU LGPL]:
  • AudioCoding
  • Mp3splt [GNU GPL]
  • Mp3Wrap [GNU GPL]
  • Alba Extractor [GNU GPL]
  • PeerCast [GNU GPL]
  • GNUMP3d [GNU GPL]
  • Mp3 Tag Tools [GNU GPL]
  • MusicBrainz Tagger [GNU GPL]
  • GramoFile [GNU GPL]
  • FFmpeg [GNU LGPL]
  • JAZZ++ [GNU GPL]
  • Mixere [GNU GPL]
  • Open Sound World [Other/Proprietary License]
  • split3pm [No license]

Business Software

  • Sequoia ERP [MPL]
  • SugarCRM [MPL]
  • vtiger CRM [MPL]
  • webERP [GNU GPL]
  • Open For Business [MIT]
  • ERP5 [GNU GPL, GFDL, GPDL, GPPL]
  • GNU Enterprise [GNU GPL]
  • Compiere ERP and CRM [MPL]
  • SQL-Ledger [GNU GPL]
  • osCommerce [GNU GPL]
  • Quasar Accounting [GNU GPL]
  • TurboCash [GNU GPL]
  • GLPI [GNU GPL]

CAD software and Electronic Design Automation (EDA)

  • BRL-CAD [BSD/GNU (L)GPL]
  • PythonCAD [GNU GPL?]
  • XCircuit [Artistic License]
  • gEDA [GNU GPL]
  • Sailcut CAD [GNU GPL]
  • TinyCAD [GNU LGPL]
  • KICAD [GNU GPL]
  • Qucs [GNU GPL]

Calendar Software

  • WebCalendar [GNU GPL]
  • Sunbird [MPL/GPL/LGPL]

CD Writing

  • Infra Recorder [GNU GPL]
  • cdrtfe (cdrtools Front End) [GNU GPL]
  • CDRDAO [GNU GPL]
  • CDRECORD
  • CDRTools Win32 binaries [GNU GPL]
  • Cdrtools with SPTI
  • SoftCDWriter
  • jCDWriter [GNU GPL]
  • Dirk Paehl's site (he claims it's open source, but I can't find the source anywhere... probably it's freeware...)

Compression/ZIP

  • jzip.org [GNU GPL]
  • 7-Zip [GNU LGPL]
  • Zzip [GNU GPL]
  • Info-ZIP
  • GreenEye (can anybody provide me the official GreenEye link?)
  • BiGZiP [GNU GPL or LGPL]
  • Open-source ARJ [GNU GPL] Ultimate Packer for eXecutables (UPX) [GNU GPL]
  •  

Databases

  • Ingres [CA Trusted Open Source License]
  • MySQL [GNU GPL]
  • PostgreSQL [BSD]
  • DBDesigner [GNU GPL]
  • Database Design Tool [GNU GPL]
  • Firebird [InterBase Public License]
  • FlameRobin [Other/Proprietary]
  • SAP DB [GNU GPL and GNU LGPL]
  • FutureSQL [GNU GPL]
  • InterBase [InterBase Public License]
  • OpenOfficeorg BASE [GNU GPL/LGPL and SISSL]

Desktop Environments & Windows shell replacements

 

  • BlackBox For Windows [GNU GPL]
  • bbLean [GNU GPL]
  • CyGNOME [GNU GPL]
  • CyGNOME 2 [GNU GPL]
  • Geoshell [GNU GPL]
  • KDE-Cygwin [GNU GPL]
  • LiteStep [GNU GPL]
  • SharpEnvironment [GNU LGPL]
  • Virtual Dimension [GNU GPL]
  • xoblite / Blackbox for Windows [GNU GPL]
  • DM2 [GNU GPL]

Dictionaries

  • jDictionary [LGPL]
  • Podo dictionary [GPL]
  • JaLingo [???]
  • Freedict:
  • Hyperdictionary
  • Ergane
  • ITRANS [???]
  • Babiloo [GNU GPL]

Drivers/Hardware

  • WDM bt848/bt878 video adquisition driver [LGPL]
  • RadeonTweaker [GNU GPL]

Educational

  • Childsplay [GNU GPL]
  • Claroline [GNU GPL]
  • dokeos [GNU GPL]
  • GCompris [GNU GPL]

Encyclopedia

  • Wikipedia

FTP clients

  • FileZilla
  • ncftp
  • TLSWrap [???]
  • PhatPlanet [???]
  • JFtp [GNU GPL]

Firewall & NAT

Firewall:

  • Simple TDI Based Open Source Personal Firewall [GNU GPL]
  • DeleGate [Other/Proprietary License]
  • PktFilter [BSD License] (also has a SourceForge.net project page)
  • IP|Screen (site down, development probably stopped. Anybody who can point me to the new location???)
  • CodeSeeker [GNU GPL] (download it here)
  • Winsock Firewall [GNU GPL]
  • IP Filter Firewall [GNU GPL]
  • WIPFW [BSD]
  • NAT:

  • Pseud IP Masquerade (PIPMasq)

File systems (drivers)

  • Explore2fs [GNU GPL]
  • Ext2 (Linux) File System Driver for Windows NT 4.0 [LGPL]
  • Ext2fsd [GNU GPL]
  • FFS File System Driver [GNU GPL]
  • FSDEXT2 [GPL]
  • rfstool [GNU GPL]
  • YaReG [GNU GPL]

Graphics

  • The GIMP [GNU GPL]
  • ImageMagick [Other/Proprietary License]
  • Sodipodi [GNU GPL]
  • Inkscape [GNU GPL]
  • Synfig [GNU GPL]
  • POV-Ray [Other/Proprietary License]
  • Dia [GNU GPL]
  • OpenFX
  • Blender [GNU GPL or BL license]
  • AutoTrace [GNU GPL]
  • CopyRightLeft [GNU GPL]
  • imgv [GNU GPL]
  • restoreInpaint [GNU GPL]
  • Wings 3D [BSD]
  • Art of Illusion [GNU GPL]
  • Irrlicht Engine [zlib/libpng License]
  • Aqsis [GNU GPL]
  • Nebula [MIT]
  • Skencil [GNU GPL]
  • Paint.NET [modified MIT]
  • Jahshaka [GNU GPL]
  • hugin [GNU GPL]
  • potrace [GNU GPL]
  • jhead [GNU GPL]
  • Tux Paint [GNU GPL]
  • GLE [GNU GPL]
  • K-3D [GNU GPL]
  • ASCII Generator dotNET [GNU GPL]

Instant Messaging

  • Gaim [GNU GPL]
  • SIM-IM [GNU GPL]
  • Miranda IM [GNU GPL]
  • aMSN [GNU GPL]
  • Psi [GNU GPL]
  • Exodus [GNU GPL]
  • WinJab [GNU GPL]
  • LLuna2 [GNU GPL]
  • wxSkabber [Aladdin Free Public License]
  • CenterICQ [GNU GPL]
  • aiMutation [GNU GPL]
  • Coccinella [GNU GPL]
  • Tkabber [GNU GPL]
  • Ayttm [GNU GPL]
  • BuddySpace [JOSL]
  • Gabber 2 [GNU GPL]
  • TSIM [GNU GPL]
  • BitlBee (gateway to IM networks) [GNU GPL]

Internet Voice chat

  • OpenH323 Project
  • Speak Freely [GNU GPL]
  • Ekiga.org [GNU GPL]
  • AsteriskWin32 [GNU GPL]
  • IAX Phone [GNU GPL]
  • SIP VoIP:

  • PhoneGaim [GNU GPL]
  • Shtoom [GNU LGPL]
  • SIP COMMUNICATOR [Apache Software License]
  • sipXphone [GNU LGPL]
  • sipXezPhone [GNU LGPL]
  • SIPp [GNU GPL]
  • wengo [GNU GPL]

IRC clients

 

  • X-Chat 2 [GNU GPL]
  • KVIrc [KVIrc License]
  • savIRC [GNU GPL]
  • BitchX
  • BoxedIrc [GNU GPL]
  • HydraIRC [Other/Proprietary License]
  • Bersirc [Q Public License]
  • Mozilla's ChatZilla [MPL, NPL]

Mail & News

  • Mozilla [NPL/MPL/LGPL/GPL]
  • Mozilla SeaMonkey [MPL, NPL]
  • Sylpheed-Claws
  • MicroPlanet Gravity [BSD]
  • Athea
  • Mahogany
  • Polarbar Mailer
  • Magic Mail Monitor 3 [GNU GPL]
  • Phoenix Mail
  • MailReactor [GNU LGPL]
  • RoundAbout [GNU GPL]
  • AmphetaDesk

 

Anti-Spam:

  • Mailfilter [GNU GPL]
  • Spamihilator [GNU GPL]
  • SpamBayes [Python Software Foundation]

Media Players (audio)

  • Delphamp [GNU GPL]
  • Zinf [GNU GPL]
  • LongPlayer [GNU GPL]
  • CoolPlayer [GNU GPL]
  • SnackAmp [GNU GPL]
  • NotifyCD [GNU GPL]
  • Winamp Radio Scheduler
  • MP3Gain [GNU LGPL]
  • MPlayer [GNU GPL]
  • MPLayer Control [GNU GPL]
  • Mixxx [GNU GPL]
  • Songbird [GNU GPL]
  • foobar2000 [Other/proprietary]

Media Players (video)

  • VideoLAN [GNU GPL]
  • Media Player Classic [GNU GPL]
  • Xine (Windows binary can be downloaded here) [GNU GPL]
  • MediaPortal [GNU GPL]
  • MPlayer [GNU GPL]
  • GPAC
  • Vitessa [GNU GPL]

Media Players (codecs)

  • ffdshow (DirectShow decoding filter for decompressing DIVX movies) [GNU GPL]
  • ffvfw (MPEG-4 Video for Windows codec) [GNU GPL]
  • AC3Filter [GNU GPL]
  • XviD [GNU GPL]
    • Koepi's XviD binaries [GNU GPL]
    • Nic's XviD binaries [GNU GPL]
    • uManiac's XviD binaries [GNU GPL]
  • MediaCoder [GNU GPL]
  • Theora [BSD-style]

Networking tools

  • OCS Inventory [GNU GPL]
  • Packetyzer [GNU GPL]
  • WinDump [BSD]
  • Analyzer [BSD]
  • Ethereal Network Analyzer [GNU GPL] (deprecated)
  • Wireshark [GNU GPL]
  • Packetizer [GNU GPL]
  • Nmap [GNU GPL]
  • Show Traffic [BSD]
  • daSniff [no license]
  • Network Game Detect [BSD]
  • Port scanner [GPL]
  • ngrep [Other/Proprietary License]
  • Knocker [GNU GPL]
  • Winip [Artistic License]
  • NetBios Scan [GNU GPL]
  • NetBIOS Enumerator [GNU GPL]
  • OpenVPN [GNU GPL]
  • DeeEnEs [GNU GPL]
  • Dynksys Dynamic IP Updater [GNU GPL]
  • MyDyndns [GNU GPL]
  • SSL-Explorer [GNU GPL]
  • Hardscan [GNU GPL]
  • tcping [GNU GPL]
  • mturoute [Public Domain]
  • tsb [GNU GPL]
  • Scapy [GNU GPL]
  • OpenRSM [GNU GPL]

NTP clients

  • NetTime [BSD]
  • NIST Internet Time Service [Public Domain]

Office tools

  • OpenOffice.org [GNU GPL/LGPL and SISSL]
  • OOExtras [LGPL]
  • OOo Label Templates [GPL]
  • AbiWord [GNU GPL]
  • PDFCreator [GNU GPL]
  • qvPDF [GNU GPL]
  • pdftk, the PDF Tool Kit [GNU GPL]
  • pdfsam [???]
  • Xpdf [GNU GPL]
  • GUIPDFTK [GNU GPL]
  • PDFTOHTML [GNU GPL]
  • LyX [GNU GPL]
  • LaTeX:
    • MikTeX
    • fpTeX
    • TeXnicCenter
    • AucTeX [GNU GPL]
    • VIM-LaTeX [GNU GPL]
    • TeX Live
    • proTeXt
  • WinDjView [GNU GPL]
  • ganttproject [GNU GPL]
  • Open Workbench [MPL]
  • Scribus [GNU GPL]
  • gnumeric [GNU GPL]
  • gnome office [GNU GPL]
  • PowerTalk [GNU GPL]
  • MathCast [GNU GPL]

Operating Systems

  • FreeDOS [GNU GPL]
  • FreeDOS-32 [GNU GPL]
  • ReactOS [GNU GPL]
  • Visopsys [???]

PostScript viewers

  • Ghostscript, Ghostview and GSview:
  • KookieJar (signature generator)
  • POPFile
  • Outclass [GNU GPL]
  • mutt [GNU GPL]
  • Unixmail [GNU GPL]
  • XanaNews [MPL]
  • Pan [GNU GPL]
  • Mozilla Thunderbird
  • PopTray [GNU GPL]
  • Blat [Public Domain]
  • slrn [GNU GPL]
  • FeedReader [GNU GPL]
  • RSSOwl [Common Public License]
  • Evolution [???]
  • si.Mail [GNU GPL]

Remote access

  • PCMan [GNU GPL]
  • PuTTy
  • MindTerm [Other/Proprietary License]
  • Tera Term
  • MSSH [GNU GPL ???]
  • WeirdX [GNU GPL]
  • RealVNC
  • TightVNC
  • TridiaVNC [GNU GPL] (discontinued)
  • Ultr@VNC [GNU GPL]
  • EchoVNC [GNU GPL]
  • BO2K [GNU GPL]
  • Synergy [GNU GPL]

Sciences and Math

Mathematics:

  • OpenStat [???]
  • Octave [GNU GPL]
  • Scilab
  • Maxima [GNU GPL]
  • wxMaxima [GNU GPL]
  • SciCraft [GNU GPL]
  • Yacas [GNU GPL]
  • The R Project
  • R Commander [GNU GPL]
  • SciViews-R [GNU GPL]
  • JGR (Java Gui for R) [GNU GPL]
  • SciPy [BSD license]
  • Rlab (no longer under active development)
  • GAP [GNU GPL]
  • MayaVi [BSD]
  • PARI/GP [GNU GPL]
  • Numerical Python [???]
  • SalStat [GNU GPL]
  • MacAnova [GNU GPL]
  • Elmer [GNU GPL]

Biology:

  • GROMACS [GNU GPL]
  • GENtle [GNU GPL]
  • ClustalX
  • GeneDoc
  • E-Cell
  • Open Bioinformatics Foundation
  • BioPython
  • BioPerl
  • BioJava
  • BioRuby
  • BioSQL/OBDA
  • BioMOBY
  • BioDAS
  • Artemis [GNU GPL]
  • PyMOL [Python License (CNRI Python License)]
  • OpenRasMol [Other/proprietary GPL]
  • Bioconductor [BSD or GPL]
  • Staden [BSD]

Geographic Information Systems:

  • QGIS [GNU GPL]
  • GRASS GIS [GNU GPL]
  • MapServer [Mapserver License]
  • GDAL [X/MIT style]
  • OpenEV [X/MIT style]
  • Thuban [GNU GPL]
  • JUMP [GNU GPL]
  • Virtual Terrain Project [VTP Software Licence]

Maybe there's more on the FreeGIS site, if you find stuff, please report it.

General:

  • Celestia [GNU GPL]
  • OpenUniverse [GNU GPL]
  • Stellarium [GNU GPL]
  • GNUPlot
  • Walnut [GNU GPL/LGPL]
  • CopperCore [GNU GPL]
  • Gwyddion [GNU GPL]
  • Virtual Moon [GNU GPL]

Security, Privacy, Protection,...

  • OpenAntiVirus
  • Clam Antivirus
    • Clam AntiVirus [GNU GPL]
    • ClamWin Antivuris [GNU GPL]
    • ClamAV for Windows [GNU GPL]
  • GnuPG [GNU GPL]
  • Privoxy
  • PINs
  • GUIDClean
  • AxCrypt [GNU GPL]
  • Oubliette
  • Stunnel [GNU GPL]
  • Blowfish Advanced CS
  • Stego [GNU GPL]
  • Hide In Picture [GNU GPL]
  • WinPT [GNU GPL]
  • SSHTools [GNU GPL]
  • KeePass [BSD License]
  • Password Safe [Artistic License]
  • SnareWindows [GNU GPL]
  • TrueCrypt [???]
  • Snare Micro Server [GNU GPL]
  • Snare agent for Lotus Notes [GNU GPL]
  • Snare for IIS [GNU GPL]
  • Snare for ISA [GNU GPL]
  • Winpooch [GNU GPL]

Server software

  • Zope [Zope Public License]
  • Plone [GNU GPL]
  • NetServer [GNU GPL]
  • XAMPP [GNU GPL]

CVS:

  • CVSNT [GNU GPL]

DHCP:

  • Dual DHCP DNS Server [GNU GPL]

DNS:

  • Posadis [GNU GPL]
  • Dual DHCP DNS Server [GNU GPL]

FTP servers:

  • FileZilla server
  • War FTP Daemon (Version 3) (still very alpha-code!)
  • AnomicFTPD [GNU GPL]
  • Pure-FTPd [GNU GPL]

Identd:

  • Ident server [BSD]

Jabber servers:

  • jabberd [JOSL and GNU GPL]
  • ejabberd [GNU GPL]
  • Jive Messenger [GNU GPL]
  • OpenIM [BSD]

Java/XML application server

  • Enhydra [Enhydra Public License]

Mail and News:

  • Hamster (Classic)
  • XMail
  • shicks! [BSD]
  • hMailServer [GNU GPL]

Webservers:

  • Apache
  • Xitami
  • Savant [GNU GPL]
  • MyServer [GNU GPL]
  • Jigsaw [Other/Prorpietary]
  • Analog [GNU GPL]

Napster servers:

  • OpenNap [GNU GPL]
  • SlavaNap [GNU GPL]

SSH-servers:

  • OpenSSH
  • copSSH (different Open Source licenses)

Other:

  • MRTG (Multi Router Traffic Grapher)
  • Squid Web Proxy Cache

SCP (SecureCoPy) clients

  • WinSCP
  • Secure iXplorer GPL [GNU GPL]

Stream Downloaders

  • gmms [GNU GPL]
  • mmsclient [GNU GPL]
  • JavaMMS [GNU GPL]
  • StreamRipper [GNU GPL]
  • StationRipper [GNU GPL]
  • ASFRecorder [Public Domain]

Text editors

  • Vim
  • GNU Emacs [GNU GPL]
  • XEmacs
  • Scintilla and SciTE
  • jEdit [GNU GPL]
  • Jext [GNU GPL]
  • WinVi [GNU GPL]
  • syn
  • SynEdit [LGPL, MPL]
  • Cream
  • SETEdit
  • ht editor [GNU GPL] (for binaries)
  • TeXmacs [GNU GPL]
  • Notepad++ [GNU GPL]
  • Notepad2 [GNU GPL]
  • UniRed [GNU GPL]
  • poEdit [MIT]

Utilities

  • HealthMonitor [GNU GPL]
  • Partition Logic [GNU GPL]
  • g4u [BSD]
  • Daphne [GNU GPL]
  • MD5summer [GNU GPL]
  • RapidCRC [GNU GPL]
  • GParted [GNU GPL]
  • Hasher [???]
  • zphoto [GNU LGPL]
  • Thotor [GNU GPL]
  • TxtPrint [GNU GPL]
  • e7NoteIt [GNU GPL]
  • Jigsaw Download (jigdo) [GNU GPL]
  • floAt's Mobile Agent [GNU GPL]
  • WinDirStat[GNU GPL]
  • Woo Shell [Public Domain]
  • JOCR [GNU GPL]
  • HovText [BSD]
  • Sayz Me [BSD]
  • Rainlender en Rainmeter [GNU GPL]
  • Bid-O-Matic [GNU GPL]
  • ctPhotoBook [Other/proprietary License]
  • Abakt [GNU GPL]
  • Really Slick Screensavers [GNU GPL]
  • RAMpagew [Other]
  • IESpy [Other/Proprietary License]
  • DiskWrite [GNU GPL]
  • GNU utilities
  • Cygwin
  • HTMLDOC
  • WinMerge

Great Freeware 

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