But I agree with cummingsc you can't be sure unless you wipe the drive. I used to just nuke and pave the system but after my years of pushing for taking all users out the local admin group on the PC mush of this problem has gone away. Now if someone gets a virus I simply copy there local files, scold them for not using their personal network drive, delete their account on the PC, delete their user folders, log back in as them and move their files back.

Unless of course my boss in all of his wisdom and experience has given the use the local admin uname and password. Then I let him deal with it.