I had the same problem after a fresh install and then a full upgrade. To fix it I had to reregister the gconf schemas (howto here: http://ubuntuforums.org/showpost.php?p=1164346&postcount=11)
Hope this helps someone... -- Configuration editor reports that no schema can be found since latest dapper updates https://launchpad.net/bugs/50150 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
