No, I don't know particularly what you are facing. Anti-virus is the most useless software, it blacklists software, patches and what-nots, on the basis of its limited central database. They slow down the pc startup and each time a drive is inserted, almost all time they are the highest cpu and memory using programs. I would say don't use them. They make their own rules. they quarantine files and programs, delete keys and stuff they feel isn't good. 
Alternatively, you could follow these simple rules:
1. don't insert un-trusted usb drives.
2. turn off autoplay for all drives.
3. don't double click the removable drives, always use explore in context menu.
4. show all files all the time, hidden and system files too, keep file extensions locked though.
5. Use soluto to get rid of files and programs. 
6. Keep your boot with minimal programs started. All extras e.g adobe reader, off
7. Try updating programs manually, the update services hog cpu and memory a lot, and start whenever they want, culprits like google update.
8. If you face a problem like you were attacked by a worm, virus, vb.net, manually remove it by searching web. Anti-virus wouldn't do any better.