I'm running Windows XP SP 3, with McAfee Security Center ver 10.5 last update 08/03/2011, Virus Scan Ver 14.5 updated 08/08/2011, Firewall ver 11.3 updated 08/03/2011, Site Advisor ver 3.4 updated 08/03/2011, Quick Clean & Shredder ver. 10.5 updated 08/03/2011. My problem started on 7/19/11 while playing a pinochile game at Yahoo games when I was logged into Windows as an Administrator (which I was usually not doing); I went to type a message on the board of the room I was in and everytime I typed a space my PC would go into hybernate mode (as if there was a power failure) this happened twice. While the pc was down I swapped out the keyboard, the space bar problem was gone. I immediately got off the internet and ran a full scan before the scan successfully and nothing was detected. About a month prior to this I downloaded Advanced System Care 4 to clean my registry, this seemed to have sped up my PC signicantly. Then the next day or so when I ran a full McAfee virus scan my PC kept crashing, whenever I did. I've manually scanned each parent folder ie. each users folder under Documents & Settings then Program Files ect. until every folder on my PC had been scanned McAfee detected nothing. I then downloaded Malwarebytes, Tdsskiller, and Super Antispyware none of these programs have detected any problems; but I still get crashes whenever I run a McAfee full virus scan. I've also been getting info logs in Event Viewer under Applications EventID 5000 Mclogevnt with the following msg:"Number of signatures in EXTRA.DAT : None; Names of threats that EXTRA.DAT can detect : None". I've been trying to find out where or how this EXTRA.DAT is generated or comes from. This Event log is generated whenever Virus Scan crashes. Up until a day or so ago I haven't seen McsvHost.exe running in my Task Manager Processes.