Remember this first though: "You only lose what you haven't backed up." So before doing anything, be sure to make copies of your important files and documents and put them on a DVD, flash drive, etc.
In addition, you haven't told us EXACTLY what the problem is with the computer is? Make and model? Operating system used? Why you think it's a virus that caused the issue? Did your antivirus detect a SPECIFIC name for a virus? The more information you give us, the better informed our answer will be.
Next, if you're thinking of using System Restore (Open the Control Panel, then the "System" icon, then the "System Protection" option on the left side of the screen, then the "System Restore" button) in the recent operating systems such as Windows 7, 8, & 10 shouldn't cause your personal data to be removed. This process takes your computer back to a time when things were good,,,, as long as your System Restore points take you back that far.
If you're thinking of using System Reset on Windows 10 (Settings-Update and Security-Recovery-Reset this PC), then there is also an option to "Keep my Files" but "reset" will remove apps and settings and is a little more "drastic" than System Restore.
So... you need to give us a little more information about your computer and what you want to do with it.
Hope this helps and let us know more.
Groif
Hi. I've found some problem in my computer. Maybe virus killed some system files. My question is, if I restore windows, should I loose all my recent personal data?
Thanks in advance.


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