What happens is that a program uses the Vista version of MSVCRT and replaces the one in SYSTEM32 - which, whilst fine on Vista machines, doesn't exactly work well with XP.
I've recently had this (its knocked out CHM viewer and my sound manager). I do suspect that GLBasic was the cause unfortunately - so it might be worth checking to make sure that uses the correct version of MSVCRT. However, saying that, it can be caused by a wide variety of other programs too.
Fortunately, trying a SFC /scannow seems to have fixed it.