• Windows Vista 64-bit is an operating system that runs on 64-bit processors. Some software programs that work on earlier versions of Windows (16-bit and 32-bit versions) do not work on Windows Vista 64-bit. Support for software changes often; check with a software manufacturer to determine compatibility.
  
  

Antispyware and Antivirus

• There are several programs built to protect your computer from harmful malware and viruses that do not work on Windows Vista 64-bit. These include Spyware Doctor v.4.0.0.2620, McAfee VirusScan Plus 2007, Dr. Web v4.33 and Avira AntiVir Workstation 7. There may be newer versions of these programs that work, and there are other security applications that do work on 64-bit Vista.
  
  

Audio and Media

• Mplayer, JetAudio 6.2x and Quicktime Player 7 do not function properly in Windows Vista 64-bit. They may install, but files do not tend to play normally in these programs. Audio programs like Phillips Sound Agent 2, MTV Music Generator and Easy Audio Editor either cannot install or will not run on this operating system.
  
  

Games

• There are many games that will not play for various reasons on Vista 64-bit. These games include Ankh II: Hearth of Osiris, Dawn of War: Dark Crusade, Caesar III, Dark Messiah of Might and Magic, Multi Theft Auto v1.1, Second Life, The Bard's Tale and many others. For some of these games, there are patches that may help, but in most cases the games must be played on earlier operating systems.
  
  

Graphics and Design

• Some graphics and design programs that do not work in Vista 64-bit are Corel Draw 8 and Corel Paint Shop Pro Photo IX, Fractint, AudioCAD 2006, Microsoft Picture It! 2002, MangaStudio EX 3.0 and ACDSee Pro v9.0b55. Many of these programs have later versions that are compatible.