Glary's registry module politely offers a backup before it repairs - good design, honestly credited. But that undo button has limits every user should know before trusting it. Here is the full safety stack, in the right order.
Most cleanup disasters are not caused by bad tools but by missing undo buttons. Glary Utilities handles this better than many rivals - it can back up its registry changes and reverse them from inside the program. This page grades that protection honestly: what the tool's own backup really covers, why a Windows restore point must still come first, and the one category of files no cleaner should ever be allowed to delete.
The three layers do three different jobs. The tool's own undo is the smallest of them - useful for reversing its changes, useless if the drive itself fails.
Before the Registry Repair module changes entries, Glary offers to save a backup of what it is about to modify, and its changes can be reversed from inside the program afterwards. This is the right design, and it deserves honest credit: many cleaners in this category historically deleted first and apologised never.
But be clear about the scope of that undo:
So treat it as a convenient undo button for small regrets, not as a backup strategy.
create a restore point, then press Enter.Layer two is the tool's own backup: always accept it when offered, and after a repair, restart and test your main programs the same day - undo is easy while the change is fresh and remembered. Layer three is your real backup: documents, photos and work files copied to an external drive or cloud, maintained whether or not you ever run a cleaner.
And the rule that sits above the whole stack: never let Glary - or any cleanup tool - delete restore points, backup folders or previous Windows installation files as part of a cleanup. A suite that eats your safety net to free space has the trade exactly backwards. Check the cleanup category list, untick anything that smells like a backup, and keep the net intact.
See how the backup prompt appears inside the repair flow in the video tour.
Watch Full VideoInside the program's own data on the same PC, listed in its restore/undo area where previous changes can be reversed. Because the backup sits on the same drive, it protects against a bad repair decision - not against disk failure, theft or a Windows install that no longer boots.
Start with the tool's own undo for that repair session - it is the most surgical reversal. If the problem is wider, or the program will not open, use System Restore to return to the restore point you created before the cleanup. That is exactly why the restore point step is never optional.
No. Old restore points are the cheapest insurance on the PC, and Windows manages their total size automatically through the System Protection settings. If space is truly tight, reduce the reserved percentage there yourself - never hand the decision to a cleanup run.