As Coreece said. But mind what you concider personal files. If you downloaded something with a virus and you back it up, you will be in the same boat the moment you open the file.
The first thing you should do after wiping the harddrive and installing your OS is run your OS update program. Once you have all the updates added, install your antivirus software. Nowadays it really doesn’t matter which one as long as you get on that provides weekly updates.Google “Antivirus” and you get many”Top 10″ lists. Read the reviews. Some free ones out there run in the top 5, above Norton and McAffee.Keep this software running at all times.
Then you install all your programs and their updates. Run a full backup of your PC. If you have the tools, now would be a good time to image your harddrive (you can then use the image to save serious time rebuilding your harddrive when something like this happens again). Thenbefore you add the backedup personal files, run a full viruscan on those files.
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