You need to protect your computer system from the viruses attack. If the viruses come inside to your computer system, it could be losing your folder or your important documents. There are a few actions you can do to protect your computer system from viruses, as folows:

1. Installing the Antivirus programs to your computer that have a good reputation, likes McAfee, AVG, Kaspersky, Norton Antivirus, Panda Antivirus, etc. Choose one of them and always updates the program.
2. Activated the Firewall feature on windows, or using the others which has the related programs.
3. Always scanning the virus for each the new programs or the others files that may be contained the code that can be executes before or after running it.
4. Do a periodic scanning for viruses and activated the feature on access scanner at Windows Start up.
5. Do a periodic backs up to your important documents.
6. Unactivated the Autorun Setting, because the virus usually comes inside the system from it.
7. Do not open your email if you do not know who has sent it. Because the virus usually comes inside from email with attractive words.