How to Backup The Windows Registry
The Windows Registry stores various settings about Windows and installed applications. Editing the Registry can be a great way to customize Windows, but improper editing can cause severe problems. Before you edit the Registry you should back it up to be safe.
Follow these simple steps to backup the Registry.
Go to Start | Run, type
regedit and press Enter
Click on the File menu
Click on Export...
Find a location and chose a name for your backup, then make sure that
All is selected and click OK.
It might take a minute or two. When it is finished you can close the Registry Editor or continue editing.