Microsoft has decided not to release Windows XP Service Pack (SP) 3 to Windows Update and the Microsoft Download Center as planned on April 29. The reason? A last-minute compatibility issue with a Microsoft application — Microsoft Dynamics Retail Management System (RMS).
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The download links direct from Microsoft that are floating around the net are valid. And yes, it is the exact same file that Major Geeks has had posted. If you ain’t running the above software then go for it. I’ve had it running on 4 machines for some time now without any issues.