I have two courses, created the same day last January, and upgraded from Moodle 1.9.9 to Moodle 2.0 in June.
I am currently using Moodle 2.0 Preview 4+ (Build: 20100809).
I tried to edit the course settings to allow guests and could not find the option. For some reason one course has the option to allow guests and the other course does not (see screneshot bellow). The course setting on the left has the Guest Access option and the course setting page on the right does not.
Any suggestion as to how to fix this. I searched the dattabase and compared the two courses, but I don't see a field that turns this ON/OFF.
Clarence