If you are still running Windows XP SP2 or Windows Vista SP1, its time to upgrade your PCs. As support for Windows Vista Service Pack 1 (SP1) ended on July 12, 2011 and support for Windows XP with Service Pack 2 (SP2) ended on July 13, 2010. If you're running one of these versions after support ends, you won't get security updates for Windows.
When a product reaches the end of support, it no longer receives security updates which can help protect it from malicious software as well as other software updates which can help improve the reliability of Windows.
End of support refers to the date when Microsoft no longer provides automatic fixes, updates, or online technical assistance. This is the time to make sure you have the latest available service pack installed. Without Microsoft support, you will no longer receive security updates that can help protect your PC from harmful viruses, spyware, and other malicious software that can steal your personal information. For more information go to Microsoft Support Lifecycle.
Install Windows XP SP3:
Windows XP SP3 includes all previously released updates and a small number of new updates. It won't significantly change the Windows XP experience. Get Windows XP SP3
Install Windows Vista SP2:
Windows Vista SP2 includes support for new types of hardware and includes all of the updates that have been released since Windows Vista SP1. Get Windows Vista SP2
If you are unsure of the version of operating system and service pack installed on your system, please visit: http://windows.microsoft.com/en-us/windows7/help/which-version-of-the-windows-operating-system-am-i-running
Windows Vista and Windows XP has newer service pack available for free that is still supported. For complete information about the end of support for various Windows versions, please visit:
Lifecycle policy if I purchase a PC with Windows already installed:
When Microsoft launches a new version of Windows, we will continue to allow OEMs to sell PCs pre-installed with the previous version for up to two years after the launch date of the new version. Certain OEM versions of Windows products include Downgrade Rights (as outlined within the software license terms). Downgrade Rights make it possible to use a previous version of Windows instead of the licensed software preinstalled on a new PC.
See Downgrade Rights for additional details.
Lifecycle policy if I purchase Windows as a packaged product:
We will continue to allow retailers to sell the previous version of Windows for a year after the launch date of the new version.
Lifecycle policy for versions of Windows purchased through Volume Licensing:
For Volume Licensing programs, licenses will continue to be available through Downgrade Rights after the end of general availability. General availability of licenses for the previous version of Windows will cease as soon as the new version is available. However, we will make media available for the current version as well as the previous two versions.