Help Cant start or reply to any forum threads

[bada_bing]

If I can get a bit of help on an issue that just recently popped up on one of my sites. The issue is that none of my usergroups can reply or post new threads in any of my forums. As an administrator I can post or reply to add forums but non of my other groups can.
I have looked at my usergroup and forum permission's which shows that these other groups can post and reply to threads. I have also disabled all plugins with no results, awe I have also tested with the VB default style with same results. Can you please advise to
what might be causing this please and what else I can check that I may of missed.

I have included a screenshot of what it looks like when I try and start a new thread, I cant type in the message field.