Virus on my Hard drive. Can someone help?

A couple months ago, I plugged my External Hard drive into a PC and it got a .scr virus or something like that.. It changed my doents into shortcuts. I look at the properties for it and it syas i'm using 20gigs of space (because of my games) but I can't find them anywhere! I tried looking at hidden folders and nothing. It's like an invidible barrier that won't let me access my files... I've tried scanning and eliminating the virus (which I did) but it isn't fully removed (I used Malaware Anti-bytes) -- How can I get this off?