Hi Sapphire,
Dumprep.exe is a standard file that lives in your Windows directory. (c:\windows\system32) - AT said she found it, you probably will find it in yours too (at least for XP).
Mostly we never know it's there until it springs into action one day.
When you get certain types of errors, it tries to install itself as a startup item to protect you from such errors in the future (supposedly...dunno how useful it really is). You'd only find it in the Task Manager if you'd had such an error at least once and it had installed itself. This is my understanding.
It isn't a virus, just an annoyance. See my message to Ron.