The application called ERUNT (larshederer.homepage.t-online.de/erunt/) can backup your registry in such a way that you can actually restore it if you run into problems. Contrary to other information online, the "export" function in "regedit" does not do that. And sadly, a Windows "restore point" does not do that either.
According to the author of ERUNT (Lars Jan/2010), an incompatibility of ERUNT with Windows 7 results in the
In addition, Vista and Windows 7 won't allow a user to run ERUNT directly. The secret of running ERUNT is to create a shortcut for either the program (ERUNT or AUTOBACK) or a batch program. You do NOT have to turn off UAC User Account Control to get it to work.
Batch Program to Backup your Registry (using ERUNT)
The batch program below will backup the Registry using a program called AUTOBACK (ERUNT for command line use). It keeps only the last 6 backup folders, deleting the oldest as you create a new backup. The subfolders are named with the date and time of the backup and contain all the files you need to restore the registry if something goes wrong. (A complete system backup is best of course, but ERUNT registry backups are faster and simpler for frequent use.)
The part of the command line after the second quote mark contains the command arguments described in the "How to" as well as the ERUNT "Detailed Information" document. If you want to run a backup before (and after) you change something in your system, a Batch Program is a better choice as it allows you customize the backup more easily. (It's good for scheduled backups too - much simpler to edit a batch file than a scheduled task!)
Use the code below in a text editor to create a batch program called REGISTRYbackup.bat. The first line is just a comment.Edit the second line to match YOUR system paths. (C:\Windows|ERUNT was chosen to store the backup folder/files because it is accessible from the Windows Recovery Console.) Notice the second line is really just one line and wraps so you can read it.
Now you can run this shortcut to backup your registry whenever you like. You will still be asked "Do you want to allow the follwing program to make changes to this computer?" but it will otherwise run at Administrator level to completion. You may wish to edit the permissions on the AUTOBACK.EXE and ERUNT.EXE. (Right-click, select Properties) if you wish to run the batch program automatically (Task Scheduler, Startup folder).
Please Email me if this doesn't work in your particular system setup. I may have changed other settings that affect this backup.