1st Open the windows Task Manager go to start search bar and type Task Manager or simply (CTRL-ALT-DEL).
2nd At the Task Manager, look in the "processes" tab. At the left-hand process listed column, see if the named mstre6.exe or fbtre6.exe (or other virus name) is there or both, if in there, your computer is infected and the virus is currently active in your system.
Important: If your Windows Task Manager doesn't open even hitting CTRL-ALT-DEL, or response but slowly or appears nothing at all, the system or your computer is infected with a virus or spyware or malicious software, even if not the koobface virus.
Kaspersky Anti-Virus 2011 1-User
McAfee Antivirus Plus 2011 3-User