Found my own solution:
Problem: Corrupt Firefox Profile extension files
Solution: Delete the following extensions from the Firefox Profile Folder:
Extension.cache
Extension.rdf
Extension.ini
To locate Firefox Profile folder go here and select instructions for your
OS:
http://kb.mozillazine.org/Profile_folder_-_Firefox
Those extensions will be recreated upon running Firefox. Now reinstall the
addon and Presto!
Locating Firefox Profile can be difficult because the AppData folder is
hidden. Follow instructions on how to show hidden files and folders in
Windows Explorer. TOOLS>FOLDER OPTIONS>VIEW TAB>check "show hidden files
folders"
Worked like a charm. Sorry I wasted anyone's time, but maybe this thread
will help someone else.
Matt Walker
"Matt Walker" <> wrote in message
news:5D1174BC-798D-4518-819D-...
> I have Windows Vista Home Premium Edition SP2 32bit. I use Firefox and
> recently installed an Add-on called AdBlock Plus 1.1.1 , but keep
> receiving the error: "Not compatible with with Firefox 3.5.5"
>
> I have many friends who are using Windows XP and are running Firefox 3.5.5
> and they don't get this error so I'm wondering if anyone know if this
> conflict between AdBlock and Vista.
>
> Thanks for any help,
>
> Matt