Before any modification in the registry of windows, it is advised to make a back up of your Windows registry in case of any mishap.

To make a backup of your registry

Windows 7/Vista

1- Click Start type systempropertiesprotection and press Enter. Enter administrator password if asked.

Alternatively right click on Computer and click on Properties

then click on System Protection.

2- Now wait for Windows to search for available disks and the most recent restore points. Click on Create.

Type a name for restore point and click Create.

After that click on OK.

Windows XP

1- Press Windows key+R, now type %SystemRoot%\system32\restore\rstrui.exe and click OK

2- When the welcome screen loads, click on Create a restore point, now click Next.

3- On this page type a name for the restore point and click Create.

 Now click Close.

How to Restore

If your system refuses to boot in a normal mode, you can always start it in safe mode. To start your computer in safe mode press F8 at start up (before windows boot) then you will be presented with boot options for Windows, here you can select safe mode.

Windows 7/Vista

1- Click Start type systempropertiesprotection and press Enter.Enter administrator password if asked. Alternatively right click on Computer and click on Properties, then click on System Protection.Now wait for Windows to search for available disks and the most recent restore points. Now click on System Restore.

2- In the system restore dialog box, select choose a different restore point.and click Next. Click on Confirm and then click Finish System Restore, Windows will provide you with recommended restore point

Select Choose a different restore point if you want to and click next (select you desired restore if your have chosen 2nd option in the previous screen), now click Finish, this will restore the selected Windows 7/Vista Configuration. After the restart click OK, when System restore confirmation page appears.

Windows XP

1- Press Windows key+R, now type %SystemRoot%\system32\restore\rstrui.exe and click OK

2- When the welcome screen loads, click on Restore my computer to an earlier time and click Next. Here you will be presented with calender like view, here you can select a date and choose the restore you have created manually or automatically. Dates with a system restore are bold.

 Now click Next Click OK on the if a message appears.

Now the system restore will restore the Windows XP to the previous Windows XP configuration and restarts the computer. When the computer restarts, clock OK on the System Restore confirmation page.