Microsoft Puts Vista SP1 and XP SP3 On Hold
Monday May 5, 2008
Windows Vista SP1 has been available for a while, but they just recently began to push it out via Automatic Updates to systems that did not yet have it. Some customers then learned the hard way that one of the changes in the way Vista works with SQL Server databases may cause data corruption for certain Microsoft Dynamics products. The latest Service Pack for Windows XP, SP3, is also on hold pending a fix for the data corruption issues. For the record though, this issue seems related specifically with the Microsoft Dynamics CRM software, so the vast majority of users have nothing to be concerned about. This PC World article has some more details about the issues.

Comments
I have already downloaded sp3 for xp and it works just fine not on auto update