ITunes issue (registry broken)

Hello folks,

Folks, I'm trying to update iTunes, and I just realized that my program is messed up, probably because of some registry cleaner I've used...

I can't repair, uninstall or even reinstall it.

It always shows these errors:



Then this one:



Then it says it didn't alter the system, and doesn't install.

I don't want to format my PC because of this...

I've tried installing/repairing/uninstalling in safe mode, and my account has administrator privileges, and I've tried the "Run as admin" option, no luck. I tried a system restore too, but no luck as the latest restore point is from 6 days ago.

I guess it was caused by some registry cleaner software, probably CCleaner... The bad part is that I declined the back up request.... (yes, I'm dumb and I've learned a life lesson after this)

So, do you guys have any idea of how to solve this?

Thanks in advance.