Windows stores many application and system settings in the registry. A saved .reg backup can restore previously exported keys and values after an unwanted configuration change.
The registry stores configuration as keys and values inside hives such as HKEY_LOCAL_MACHINE and HKEY_CURRENT_USER. Importing a .reg export merges its entries into the live registry, overwriting matching values without automatically removing entries created since the backup.
An incorrect backup can break applications or prevent Windows from starting. This method requires a working Windows desktop and a trusted .reg export for the intended computer and user account; a registry export is not a complete system backup or a recovery method for a computer that cannot boot.
Steps to restore the Windows registry from a backup:
- Launch regedit from the Run dialog (Windows + R).
- Approve the Registry Editor consent prompt from Microsoft Windows with Yes.
Elevation permits changes to system-wide registry settings. If a different app or publisher appears, cancel the prompt.
- Back up the current state of the affected keys to a separate .reg file.
A separate export preserves the current values if the older backup makes the problem worse. It must not overwrite the backup being restored.
- Open the backup .reg file as text in Notepad.
A Run entry such as notepad C:\RegistryRestoreDemo\before.reg opens the named file for inspection without importing it; the path depends on where your backup is stored.
- Check the backup's key paths and value data against the settings you intend to restore.
A .reg file can also contain deletion instructions. If the file contains unfamiliar keys, another user's settings, or unexpected deletions, stop before importing it.
- Open the File menu in Registry Editor.
- Select Import.
- Enter the backup's full path in the File name field.
- Select Open to import the chosen backup.
Importing overwrites matching live values immediately. The key currently selected in Registry Editor does not limit the import; the paths inside the file determine what changes.
- Dismiss the successful-import message with OK.
If Registry Editor reports an error, the import may be incomplete. A success message is required before treating the import as finished.
- Refresh the restored key in Registry Editor with F5.
If another key is selected, the address bar accepts the key path from the backup.
- Compare the restored value names, types, and data with the backup.
The illustrated Preference value has returned from Changed to Before change. Some settings take effect only after the affected application restarts, a sign-out, or a Windows restart, depending on the setting.