In an article posted in the section of its Web site, Microsoft says that Service Pack 2 may not work with computers running Advanced Micro Devices' 64-bit microprocessors. The Redmond, Wash.-based company said earlier that owners of such PCs may want to bypass the update completely, but has now come up with a workaround.
AMD's 64-bit chips include the Athlon 64 for PCs and the Opteron for servers.
A Microsoft representative declined to comment directly on the AMD-related issue but said the company "continually investigates all issues and vulnerabilities" reported to it regarding SP2 and other products.
However, an AMD representatives said the chipmaker believes the problem has only occurred, so far, with one application, Sigma Designs' Realmagic Hollywood Plus DVD Decoder. Microsoft also identifies the application as being able to cause the problem.
Microsoft said in its advisory that PCs with 64-bit AMD processors may restart repeatedly after installing Service Pack 2, if those machines are also configured to enforce so-called data execution prevention (DEP) and contain hardware that requires a driver software known as Mpegport.sys. Sigma Designs' Realmagic Hollywood Plus DVD decoder application is one such application that uses the driver, the software maker said.
Microsoft says users may be able to resolve the problem by configuring a so-called DEP exception. AMD also recommends that people affected by the problem do so. Earlier, Microsoft had advised AMD users to remove SP2 altogether.
The AMD problem is the latest in a slew of issues that have dogged SP2 since it was first released to PC manufacturers at the beginning of August. By mid-month, Microsoft had detailed some 50 different software applications and games that may.
The potential for conflicts caused some high-profile businesses, including IBM, to order their employees tountil its ramifications can be better understood. Other organizations are moving forward with the update, expecting that its security enhancements outweigh the integration issues.
Microsoft hasto help IT professionals assess their software's compatibility with the update. The compatibility guide, which can be retrieved from Microsoft's , is designed to help administrators "test and mitigate application compatibility issues."