check if the application spoolsv.exe is running in your task manager. Ive heard that it was recently being used by a worm to infect the computer. Maybe the file was corrupted by the worm or quarantined by an anti-spyware program preventing it from running. For further information about this application just type spoolsv.exe in google the first website to pop will give a very good definition of the file and tell you how to fix it.