How to create backup and restore registry

To SAVE or EXPORT or BACKUP registry.

Go to START and click on RUN or hold WINDOWS key and press R to open RUN window. Type 

" REGEDIT " without double quotes and press ENTER key to open REGISTRY EDITOR.

Go to FILE menu and click on EXPORT.

Give a name and path and click on OPEN to save the registry file.

To RESTORE or IMPORT the existing backup registry file.

Considering you have already taken backup of the registry to a file, go to FILE and click on IMPORT.

Now go the location of the saved registry file. Select the backup registry file and click on OPEN to restore the previous stored registry settings.