I'd suggest sth but I'm afraid not to look like a communist.
Haha joke.
I'd say, the both posts above my are ok, but if you consider it hard to use MRT or hard to update (lol!) then just scan! If it found the virus, it sure found a file which is infected. Just delete the file manually. What's the problem?
The only times I've seen that lately, it was a window that popped up on your screen claiming that you are infected by it. In reality, all it is is a piece of crap spyware program created by some idiot trying to rip you off.
Try running combofix (do a Google search to find it) to get rid of it.