You need to go to your Folder Options menu and unhide some options.
UNCHECK box "Hide extensions for known file types
CHECK circle for "Show hidden files and folders
UNCHECK box for "Hide protected operating system files".
(I'm sure some of these were already done).
Make sure you have downloaded both oleacc.dll and the appwiz.cpl files to a place on your hard drive you can get to them (a place other than the windows folder(s).)
Now, reboot into Safe Mode.
Look in Safe Mode in the c:\windows\system32\dllcache folder for the oleacc.dll file AND while you're there, the appwiz.cpl file.
If both are present there, delete them from that folder. Replace them with the oleacc.dll and appwiz.cpl files I had you downloaded.
(Note: appwiz.cpl might not be present there (in the dllcache folder) ...it's not in my dllcache folder. BUT, if it is, you need to delete it from dllcache and replace it with the new version, as well as putting a copy of the new version in the system32 folder).
ALSO, put the newer versions of those two files in your \windows\system32 folder.
What's happening is that the dllcache folder contains versions of Windows Protected Files. If Windows detects that a deletion has occured to a protected file, it will immediately attempt to replace it with a copy it has in the dllcache folder. So, it's necessary to remove/replace the versions in your dllcache folder AND your system32 folder if you want newer versions of the files to stick. AND, this must be done in Safe Mode.
So, your tasks:
Boot to Safe Mode.
Go to c:\windows\system32\dllcache
Find oleacc.dll and appwiz.cpl in the dllcache folder.
Delete them.
Find oleacc.dll and appwiz.cpl in the system32 folder.
Delete them.
Now, copy the NEW DOWNLOADED versions I gave you for both oleacc.dll and appwiz.cpl to:
c:\windows\system32
AND
c:\windows\system32\dllcache