Microsoft Support for Windows Vista (with no service packs installed) ends on April 13, 2010, while support for Windows XP (without Service Pack 3 installed) ends on July 13, 2010. Windows 2000 support will end on July 13, 2010 as well.

There is no Service Pack 3 for the 64-bit version of Windows XP. If you're running the 64-bit version of Windows XP with SP2, you have the latest service pack and will continue to be eligible for support and receive updates until April 8, 2014.

What Does It Mean When Support for My Operating System Ends?

If you are still running a version of Windows where support has ended, it means that version of Windows will no longer receive any updates from the Windows Update or Microsoft Update site. These updates are generally provided for security reasons to help protect the PC from harmful viruses, spyware, malware, and other malicious software. Windows Update also provides new drivers for your hardware that can improve the reliability of Windows.

Hackers love to take a security vulnerability in Windows and exploit it to their advantage. So, if a vulnerability is found in Windows XP or Windows Vista and you are not running the latest service pack, you will not be protected and will be at risk.