Re: forum does not work
Ah… the famous “there was an error when creating the topic” problem.
Go to your site, and go to a group than you have individually created. (important!)
Go to groups admin –> Group Settings
Now see the little checkbox “enable discussion forum”?
Un-check it, than recheck it, and go to the bottom and click “save”
Try to create new topic now.
(all credits of Hnla for the solution)