My computer was OK one moth ago but it isnt working properly now.

It was virus free until i plugged in my USB yesterday.

My important file was deleted from dektop while i was deleting old user acounts...

If this sort of problem arises on your pc then dont worry there is easy solution for the problem.No need of money and less time
The easy way to recover your system is System Restore.


System Restore is the service which allows you to restore your PC to the previous date with the help of restore point.
System Restore helps you restore your computer's system files to an earlier point in time. It's a way to undo system changes to your computer without affecting your personal files, such as e-mail, documents, or photos.
Sometimes, the installation of a program or a driver can cause an unexpected change to your computer or cause Windows to behave unpredictably. Usually, uninstalling the program or driver corrects the problem. If uninstalling doesn't fix the problem, you can try restoring your computer's system to an earlier date when everything worked correctly.
System Restore uses a feature called system protection to regularly create and save restore points on your computer. These restore points contain information about registry settings and other system information that Windows uses. You can also create restore points manually.

System Restore affects Windows system files, programs, and registry settings. It can also make changes to scripts, batch files, and other types of executable files created under any user account on your computer. System Restore does not affect personal files, such as e-mail, documents, or photos, so it cannot help you restore a deleted file. If you have backups of your files, you can restore the files from a backup.

How to Restore System

Win7/Vista
1.To open system restore in XP you should firstly select which drive should be monitered to do so right click on computer select on system protection look down to drives and click drive c:and click on configure tick on Restore system settings amd previous version of files and click on apply
2.Go to start menu and type "system restore" on search bar click on system restore
3.Tick on Choose different Restore point.
4.Tick on show more restore points.
5.Select your Restore point and click next.
6.click finish
(warning: Do not restart computer while it is on restore process)
restore can be undone with same process selecting Undo my last Restore

You can create your own restore point when you feel you computer is fit to be restored,For that
1.right click on my computer select properties
2.Select system protection
3.select create a restore point right now for...turned on
4.Select on create give the name
5.click create

XP
1.To open system restore in XP you should firstly select which drive should be monitered to do so right click on computer select on system protection look down to drives and make drive c: to be moniter and turn of for Others
2.Go to Start/All programs/Accesories/System tools/System restore
3.Select on restore my computer to an earlier time
4.Select the date when you want to restore
5.Run Restore

You can create your own restore point when you feel you computer is fit to be restored for that
Go to Start/All programs/Accesories/System tools/System restore
3.Select on create  new restore point.
4.give name for the restore point
5.slect create