Within hours of its release, Microsoft's Service Pack 3 for Windows XP began drawing hundreds of complaints from users who claim the update is wreaking havoc on their PCs.
The problems with XP SP3, according to posters on Microsoft's Windows XP message board, range from spontaneous reboots to outright system crashes.
"My external disks are having trouble starting up, which results in Windows not starting up," complained user Michael Faklis, in a post Wednesday. "After three attempts [to install XP SP3] with different configurations each time, System Restore was the only way to get me out of deep s**t," said 'Doug W'.
Another user said the service pack prevented him from starting his computer. "I downloaded and installed Windows XP Service Pack 3 Network Installation Package for IT Professionals," wrote 'Paul'. "Now I can't get the computer to boot."
Dozens of other posters reported similar problems.
It's not uncommon for major operating system updates to cause problems. Typically, the glitches are due to conflicts with software, such as drivers, system files, or applications already resident on the user's PC. Microsoft has yet to indicate whether it will issue an update to address some of the problems, though it has done so with previous updates.
Microsoft released Windows XP SP3 to broad distribution on Wednesday. It's available from Microsoft's automated Windows Update service or as a file that can be pulled from the Download Center on the company's Web site.
The service pack should offer a number of enhancements over the current version of the OS, which Microsoft is phasing out after June 30th. It includes all updates issued since Windows XP Service Pack 2 was released in 2004, and some new elements.
Among them: A feature called Network Access Protection that's borrowed from the newer Windows Vista operating system. NAP automatically validates a computer's health, ensuring that it's free of bugs and viruses before allowing it access to a network.
Windows XP SP3 also includes improved "black hole" router detection -- a feature that automatically detects routers that are silently discarding packets. In XP SP3, the feature is turned on by default, according to Microsoft.
Additionally, Windows XP SP3 steals a page from Vista's product activation model, meaning that product keys for each copy of the operating system don't need to be entered during setup. The feature should prove popular with corporate IT managers, who often need to oversee hundreds or thousands of operating system installations.
Some users may balk at a feature in XP SP3 that prevents them from downgrading their browser from Internet Explorer 7 to the older IE 6 once the service pack has been installed. XP SP3 also won't install on systems running beta versions of the yet-to-be released IE 8.
Microsoft said the restrictions are designed to prevent system instabilities.