Microsoft has warned users of Windows XP Service Pack 3 (SP3) that they may not be able to uninstall either the service pack or Internet Explorer 8 (IE8).
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.
Microsoft programme manager, Jane Maliouta, spelled out the new situation on the IE blog. She said that users who downloaded and installed IE8 Beta 1 prior to updating Windows XP to SP3 were affected. If those users then upgrade IE8 to Beta 2, they will be stuck with both IE8 and Windows XP SP3.
A warning dialogue 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.
It's unclear how many users the warning is aimed at. Although users running Windows XP and IE8 Beta 1 could manually download and install Service Pack 3 from Microsoft's site, the company set its Windows Update service so that it didn't offer SP3 to systems with IE8 Beta 1.
Windows XP users who do have the first beta already on their machines will be offered the update to Beta 2 via Windows Update if they have Automatic Updates enabled, Maliouta continued. "A prompt in your Windows task bar will alert you when IE8 Beta 2 is ready for installation," she said.
Windows Vista users, however, will not see IE8 Beta 2 in Windows Update because update apparently cannot sniff out instances of IE8 Beta 1 and uninstall them automatically. Instead, users must remove Beta 1 manually, said Maliouta.
Several additional updates are required before installing IE8 Beta 2 on Vista, including one that, if omitted, blocks its installation entirely. That fix, a revised version of a Vista Service Pack 1 (SP1) prerequisite that earlier this year sent machines into an endless series of reboots, is also necessary for IE8 Beta 2; users with SP1 will, of course, already have it in place, but those running pre-SP1 versions of Vista must still install it.
Microsoft also spelled out a long list of IE8 Beta 2 known issues and compatibility problems in release notes it posted on its support site.
Ironically, of the nine applications called out as incompatible with the new IE8, the only two that will lock up and crash are Microsoft's.
Visual Studio.NET version 7, said Microsoft, will crash on a PC that also contains IE8 Beta 2. "No workaround is currently available," Microsoft said in the release notes.
The other Microsoft incompatible application is Windows Live Mail, formerly called Windows Live Desktop, and the desktop mail client meant to replace Outlook Express and Windows Mail. "If you install Internet Explorer 8 Beta 2, Windows Live Mail will crash when you create or reply to an email message," Microsoft warned.