Twice I have returned to my computer and Prevx had a winow popped up saying SVCHOST-EXE caused a buffer overflow. The parent path services.exe. The first time this happened Process Guard was messed up also. Had to reinstall PG. This time the sound was gone and the color of the task bar was changed. Rebooted and now it is ok. Both times the computer was on but wasn't being used. Anyone have any ideas?