It won’t work if you have a rootkit infection, but it won’t blue screen your machine either.

Microsoft has reissued Security Bulletin MS010-15 from last month to work around a problem that had occurred when a WinXP user attempted to install the patch on a machine that was infected with a rootkit. (blue screen, blue screen)

Jerry Bryant, Microsoft’s senior security communications manager lead, writing on the company TechNet blog said that the new installation packages for MS10-015 have new logic that will prevent the security update from installing on rootkit-infected systems. Microsoft also is offering guidance for those with infected machines and a scanning tool that can detect system conditions that will prevent the patch from applying itself.

Microsoft TechNet blog here.

We described the problem on the Omid’s Blog! Feb. 13 “WinXP users: hold off on installing MS010–15 [BSOD]”.