To apply System Restore in Windows 8, go to the Start screen, search "restore," press Enter, and click Create A Restore Point from the search results. In the System Properties window, navigate to System Protection, and click System Restore. In the window that appears, click Next, choose a restore point, click Next, confirm the restore point you chose, and then click Finish. The same procedure applies for Windows 7 and Windows Vista. Enter the administrator password if prompted.
If your computer is running Windows XP, click the Start button, navigate to Programs, go to Accessories, click System tools, and then click System Restore. In the window that appears, check Restore My Computer To An Earlier Time, and click Next. Select a restore point from the list with dated restore points, or click Show More Restore Points to see further dated restore points. Click Next, confirm the restore point you selected, and then click Finish.
After clicking Finish, wait a few minutes for the computer to restart. Log in, and wait a few minutes for a message confirming that Windows has successfully restored. Click Close on the dialog box that appears. If your computer cannot boot Windows normally, apply System Restore from Safe Mode.