Microsoft Corp. yesterday warned users of Windows XP Service Pack 3 (SP3) that they won't be able to uninstall either the service pack or Internet Explorer 8 (IE8) under some circumstances.

The warning was reminiscent of one Microsoft made in May, when Windows XP SP3 had just been made available for downloading. At the time, the company told users they wouldn't be able to downgrade from IE7 to the older IE6 browser without uninstalling the service pack.

In a post to the IE blog today, Jane Maliouta, a Microsoft program manager, spelled out the newest situation, which affects users who downloaded and installed IE8 Beta 1 prior to updating Windows XP to SP3. If those users then upgrade IE8 to Beta 2, which Microsoft unveiled today, they will be stuck with both IE8 and Windows XP SP3.

A warning dialog will appear to alert users. "If you chose to continue, Windows XP SP3 and IE8 Beta2 will become permanent," Maliouta said. "You will still be able to upgrade to later IE8 builds as they become available, but you won't be able to uninstall them."

She recommended that users instead first uninstall Windows XP SP3, then uninstall IE8 Beta 1; they should then reinstall XP SP3 and follow that by installing IE8 Beta 2.
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I have nothing nice to say about SP3 after all the issues I and others have had with it. I had to reload my XP to make my system work again after XP3 crash.