I know of some institutions have implemented the Windows XP SP3 Windows Update “Service Pack Blocker Tool”. This tool was meant to delay the automatic Windows Update distribution of Windows XP Service Pack 3 for a one year period. I just want to give everyone a heads up that the expiration of this “delay mechanism” is near, so you may test and verify Windows XP SP3 in your environments.
The Service Pack Blocker Tool temporarily prevented the installation of a service pack through Windows Update, typically for one year after general availability of the service pack. The upcoming expiration dates for the Service Pack Blocker Tool for Windows Vista SP1 and Windows XP SP3 are:
• Windows Vista SP1, April 28, 2009
• Windows XP SP3, May 19, 2009
After April 28th, Windows Vista SP1 will be delivered via Windows Update. And after May 19th, Windows XP SP3 will also be delivered via Windows Update.
For more information on the Service Pack Blocker Tool, please see this blog posting by the Windows product group.