What is Registry Backup exactly for?

[Minatoro]

Hello,

I recently run into a problem with CCleaner. I used it to clean my registry, and after that Windows 10 could not boot again. I could not even repair it with the usual safe-mode, reset, or restore routines. So I had to reinstall my Windows 10.

Now, I have used CCleaner to clean my registry for years, and this is the first time this happened. It might be CCleaner's fault or perhaps something else happened that day e.g. installing a video driver.

This was an eye opener for me, so I want to inquire. What is registry backup really for? Is there anyway to use it when the OS refuses to boot up? Or is it for less serious errors e.g. a messed up start menu or something of this genre; that I can fix by restoring the registry from the backup?

 

Cheers.

 

[nukecad]

You should not be regularly using any Registry Cleaner on Windows 10 or 11 - Windows 10 and 11 change the registry too often for that to be safe to do.

Yes, you might do it for years and get away with it, but eventually Windows can/will change something in the registry and that will catch you out - as you have found.

For the official Piriform advice on using CCleaners' Registry Cleaner see this: https://community.ccleaner.com/topic/59952-i-get-a-registry-error-on-ccleaner-on-windows-10-i-have-scanned-5-times/?tab=comments#comment-326804

Registry Cleaning is now an advanced tool to help fix problems, it's not something that you should use regularly.
It will not speed up your machine, or save more than a few KB of space.

A registry cleaner is a tool that should only be used if you already have a problem that you are trying to fix.
Even then it should be used carefully.
If you wouldn't manually open the registry yourself and edit things in there then generally you should leave all registry cleaners alone.

Here is Microsoft's stance on using any Registry Cleaner:
https://support.microsoft.com/en-gb/help/2563254/microsoft-support-policy-for-the-use-of-registry-cleaning-utilities

 

To answer your question of what CCleaner's registry backup is for:
It saves the registry entries that it is going to change/remove (only those ones not the full registry) so that if something does go wrong you have a chance to 'merge' them back into the registry.
It is only a chance though, sometimes the changes made mean that Windows will not let you merge it back, in which case it's probably going to mean you have to reinstall Windows.

 

[Minatoro]

Thank you for the prompt and informative answer.

Cheers.