Backup the registry with ERUNT Recovery Utility
The “Export registry” function in Regedit is USELESS for making a complete backup of the registry. Neither does it export the whole registry (for example, no information from the “SECURITY” hive is saved), nor can the exported file be used later to replace the current registry with the old one.
Instead, if you re-import the file, it is merged with the current registry without deleting anything that has been added since the export, leaving you with an absolute mess of old and new entries.
Features of ERUNT Emergency Recovery Utility: Backup the Windows NT/2000/2003/XP registry to a folder of your choice; System and current user registries selectable; Command line switches for automated registry backup and restoration; – Restore the registry in Windows 9x/Me/NT/2000/2003/XP and MS-DOS (all-in-one restore program) or the Windows Recovery Console; NTREGOPT program for optimizing the registry.
Please note that ERUNT’s development has stopped, you may like to check some other freeware, such as Registry Backup.