Before you edit the registry, export the keys in the registry that you plan to edit, or back up the whole registry. If a problem occurs, you can then follow the steps how-to restore the registry to its previous state.
How to Export Registry Keys
Click Start, and then click Juoksua. In the Run box, type “refedit” (without “) , and then click Hyvä.
On the File menu, napsauta Viedä. In the Save in box, select the boxs at the bottom the bottom according to weather you want to export all or only selected branches of the registry.
Next select a location in which to save the backup .reg file. In the File name box, type a file name, and then click Tallentaa.

How to Restore the Registry
To restore registry keys that you exported, double-click the .rreg file that you saved.