I tried to detect what was thwe problem with a PC of a friend who wasn't unable to execute Windows update and found one of the problems in a "packer.wundo.gen" infection. I tried getting rid of it with several antivirus programs (Avast, Virit, McAffe Stinger, etc.) with no results. Avast was able to spot some files infected and to apparently put them in quarantine, but after a while it all started again.
Finally I spotted ComboFix and ran it. I did not understand the log, but I think ComboFix did remove many infected files. After, I have been able to update Windows and it is now 24 hours and everything seems all right..
To day I tried to run ComboFix on my computer at home. I don't think I have malware problems, but just to be sure. I got the log and I would like to understand it. Is there someone who can help me in this ? If yes, I will attach the log file in my next messaage.