An anonymous reader writes: If you're using Windows 7 you might want to be careful about which updates you install. Users on Windows forums are worried about a new "important" update that looks a little suspect. Ars reports: "'Clearly there's something that's delivered into the [Windows Update] queue that's trusted,' Kenneth White, a Washington DC-based security researcher, told Ars after contacting some of the Windows users who received the suspicious update. 'For someone to compromise the Windows Update server, that's a pretty serious vector. I don't raise the alarm very often but this has just enough characteristics of something pretty serious that I think it's worth looking at.'" UPDATE: Microsoft says there's nothing to worry about, the company "incorrectly published a test update."