So I'm fixing a friend's computer b/c he says he has tons of pop-ups and his PC is really slow. I get over there and his PC is slow as shit.
I run AdAware SE. His definitions are 605 days old and it finds over 700 files.
I then run S&D which finds another 56 files.
I download HiJackThis! and play with that for about an hour, deleting tons of shit.
I then ask him what anti-virus software he's using so I can run that as well. He says he's not sure he has any. Ends up he doesn't. I download AVG and get this - it finds 1909 viruses.
Fix all that which takes about another hour.
I left and everything seemed to be OK surprisingly. I'm shocked that his PC was even responsive with all those problems.
Friends shouldn't let friends buy computers.