Back up the Registry
Give yourself a fall-back.
Before you start tweaking the Registry, ask yourself what you’ll do if something goes wrong. Most tweaks won’t bring your system grinding to a halt, but they may render applications unusable or result in strange behaviour you weren’t expecting. Some Registry edits are easier to undo than others as well — so make things easier for yourself (and your health) by following a multi-layered approach to taking precautions.
Before you begin, take a System Restore point, which backs up the Registry in its current state, as well as other system les. Type “system protection” into the Cortana search box, and select ‘Create a restore point’. Verify System Restore is switched on for your system drive (click ‘Con gure...’ if it’s not), then click ‘Create’. Give your Restore point a suitable name, such as ‘PreRegistry tweaks’ and click ‘Create’ again.
This is your fall-back backup. If all else goes wrong, you can access System Restore from within Windows itself (click ‘System Restore...’ from the ‘Create a Restore point’ screen), or from the list of recovery options if Windows won’t boot — choose ‘Troubleshoot’, then ‘Advanced’ and ‘System Restore’ to select the Restore point you created earlier.
It’s also a good idea to back up individual Registry keys before you start changing them — this is done from within Registry Editor. Rightclick the target key in the left-hand pane and choose ‘Export’. Again, give your backup a suitable name (and save it to your backup drive) before clicking ‘Save’. Backed-up settings are stored in the .REG format — you can restore them via ‘File > Import’ inside Registry Editor, or simply by double-clicking the le and clicking ‘Yes’ twice. These settings will overwrite your changes, restoring things to how they were.