Lost permissions on many registry keys

[redcat]

Hi, I'm on Windows 7 64 and in the last few days I've been getting A LOT of errors (mainly installations) related to reg keys. A run of Process Monitor and Regedit shows that there are many registry keys where I "can't display owner", but I am logged in as an administrator, UAC is turned off and I've never had issues!
I don't know what caused all this, the faulty keys seems unrelated (media filter, Flash, who knows what else). The problem is located in HK_Classes_Root subkeys I think.
How could I restore the permissions???

THANKS

 

[Jacee]

Have you run an Anti-virus and Anti-spyware scan?

 

[redcat]

I'll try. I actually ended up making a system restore, to the earliest point I could. The registry seems fine.