c:\windows\system32\winlogon.exe

Help please! Avast can’t remove the virus Win32:Patched-LO [Trj]

Try this

Boot time Avast Antivirus Scanning
http://www.digitalred.com/avast-boot-time.php

MBAM http://filehippo.com/download_malwarebytes_anti_malware/
update and run quick scan, then click on “remove selected” to quarantine anything found and restart

The malware name (“Patched”) implies that the original winlogon.exe (a system file) has been somehow modified (so it’s not a good idea to remove it, even if avast! allowed that, which I doubt).
It should be possible to repair the installation from Windows CD.

found this, Read the Disinfection part

http://www.f-secure.com/v-descs/trojan_win32_patched.shtml