Before It's Too Late!

I recently encountered some serious problems with my computer. I can not exactly figure out what it was but I am afraid I will lose everything if I won’t act on it right away. My PC shuts down on its own. I do not exactly know the problem. Do online backup necessary for this kind of problem?

I have talked to one friend and he told me it is a must to update the antivirus everyday. He thinks there is a problem with my operating system and it has got something to do with the virus. Oh well! It has bugged me ceaselessly so I am no longer surprised. I need to ask my friend again to have a check on my PC before it gets too late.

Sigh!