SOunds like virus. See LimeWire continually Popping up every few seconds & also Opening at System Startup about same thing most likely. Sorry that is the LW section but same applies!

You could also try http://ask-leo.com/why_cant_i_delete_this_file.html & also How to delete files from your hard-disk: download: moveonboot.exe
This program will allow you to select a file that you want to move or delete. When you reboot, the file will be moved to the location you want or if you've chosen to delete, it will be gone!