I hope I'm not breaking any forum rule!!!!! Just came up with something I though I'd share.
My mother computer which runs on free AVG detected a Trojan located at c:windows\system32\winlogon.exe named Flooder.AKE. She removed the file and was not able to logon anymore as windows kept going into loops after splash screen.
This happened yesterday. I googled it and found another 4 different topics for people that had the same issue and also started yesterday, they were more fortunate in resolving it. Apparently the file is not infected, and it's being deleted by mistake.