Feature suggestion  

If a forum permission is set No Access nobody can see and enter to that forum. How they see 404 error? Have you made any changes in No Access permission settings?

The no access setting is standard.

If the url of the private forum is shared by a user to somebody who has not the credentials to enter it will return the no permission message. If a topic url from that private forum is shared a 404 is shown. In both cases the breadcrumb is displayed.

This is undesirable in my use case because in certain of the private forums there are custom header notices (using Gvectors Ad Manager) that should not be displayed to to those without permissions to see same. The way no access is setup users who should  not even know of the existence of those forums can see those notices and forum breadcrumb.

In my opinion no access should automatically redirect non privileged users back to the main page without displaying messages etc. No access should mean exactly that.

Hi VereK,

We'll replace the 404 page to "You don't have permission to create post in this forum" error message in next version release. 

Thanks Sofy but i would prefer a redirect. One of the problems of the current method is certain email providers, such as Microsoft and Yahoo scan every link contained in the body of an email. So, when a credentialed member receives a subscription notice email, that link is immediately swarmed by bots. 

No access should mean exactly that, anybody without permission to view that forum or the topics contained therein should be 301'd back to the forum homepage.