System Restore periodically creates restore points whenever new software is installed or when a change has been made to your computer settings. You can also create manual restore points by clicking the "Start" button, then "Control Panel." Select "Back up your computer" and "Create a restore point or change settings." Select the disk which contains your computer's program files (typically, this is drive C:) then click "Create." Type a name for your restore point, then click "Create." If you experience a problem with your computer later, you can restore your computer by clicking the "Start" button, "Control Panel," "Back up your computer" and "Use System Restore to fix problems and undo changes to Windows."
If the System Restore completes successfully, all programs installed prior to the restore point will be returned to the state they were in when the restore point was created. However, any programs you installed after the restore point was created will be uninstalled. You must reinstall these programs if you wish to use them again. That said, any files which you created with that particular program will remain on your hard drive unchanged. For example, if you downloaded a photo editing program, installed it and used it to edit and save some of your personal pictures to a subdirectory of the photo editing software, the edited photographs will still be on your computer.
