Can't access any other forum

Does anybody have any idea why I am not able to post anything on any Forum other than this one? I read as much as I can and I don't see any reason why I wouldn't be able to ask a question in the rifle forum but I don't have the little plus symbol to be able to do that. I never received an email to finish signing in but obviously I'm able to post on this page. Any help would be greatly appreciated. Thank you, Richard