Five or ten years ago, the only way to restore a computer after something terrible happened to it would be to reinstall your operating system off of restore disks. These disks would come packaged with your computer and would be the only way to return your computer to normal in the event that you downloaded a virus or some other calamity occurred. Nowadays restore disks are a thing of the past. You can easily restore your Sony Vaio without a restore disk.
Restart your Sony Vaio if it is already on. If it's off, turn it on.
Press the F12 key on your Sony Vaio keyboard. This will enter the computer into the built-in restore mode. Note that depending on the model of Sony Vaio, you may have to press either the F11 key or the ESC key to enter this restore mode. This must be done before your operating system begins to load. If you see the Windows logo appear on screen, you'll have to restart and try again.
Choose the option on screen that is most appropriate to your needs. You will be presented with three options: you can either create a set of recovery discs, attempt to repair your operating system's installation, or restore your operating system. Repairing your operating system will attempt to fix your computer without deleting any of your personal files. Restoring your operating system will delete everything on your hard drive and return your computer to its original factory settings.
Wait for the restore process to complete. Depending on the type of restore you've tried, you may have to wait as little as a few minutes and as much as an hour or more. When the process is finished, the computer will automatically restart itself.