When viruses attack your computer, you may relax, because you've updated your antivirus every day. Problems will arise if your antivirus, rather than eliminate the virus but also remove the folders that contain your important files.
What is on your feelings then? confused and frustrated? Do not panic, try this:
1. From Start select Run and type "cmd".
2. If the missing folder was on drive C:, type "attrib-r-s-h / s / c"
3. Wait until the process is complete, you will see your folders again.