Installing Adobe Acrobat and Outlook Junk Mail Filter update generated an error that looks like:

Error 1402.Could not open key: UNKNOWN\Components\xxxxxxxxxxxxxxxxxxxx\yyyyyyyyyyyyyyyyyyyyyyyy

The problem, most likely is that the permissions on the key yyyyyyyyyyyyyyyyyyyyyyyy are incorrect. To resolve this, search the registry for xxxxxxxxxxxxxxxxxxxx.

It should come up under

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\xxxxxxxxxxxxxxxxxxxx

The key yyyyyyyyyyyyyyyyyyyyyyyy or more likely every subkey of xxxxxxxxxxxxxxxxxxxx is messed up. To correct this, you will likely need to take ownership of the subkeys and then correct permissions on those key. In my case, this proved to be easy because "Replacing owneron subcontainers and objects" worked (sometimes it doesn't).

Right click on xxxxxxxxxxxxxxxxxxxx choose permissions and then advanced. Click on the owner tab. Choose Edit. Make the owner "Administrators" if it is not already, and check the box that says "Replacing owneron subcontainers and objects".

Click on OK. Get back to the same dialogue through the procedure above, but go to the permissions tab. If the permissions were not already correct, you should see updated permissions in this dialogue now. Check the box that is labeled "Replace all child object permissions with inheritable permissions from this object" and click OK.

Rerun the installer. I found that a reboot is not necessary, but it never hurts.