[b]Reproduction Steps:[/b] [b]1)[/b] Visit an arbitrary public thread and make sure that your Comment Sort is set to "Popular". [b]2)[/b] Go to the forum of a Private Group. [b]3)[/b] Click the "New Topic" button. [b]4)[/b] Give it an Arbitrary Title, and an Arbitrary Body Post. [b]5)[/b] Make sure the Private check box is checked, then post the thread. [b]6)[/b] In the new thread, try changing the Comment Sort to "Oldest First", observe the 404 Error Page. [b]7)[/b] Return to the thread, then try changing the Comment Sort redundantly to "Popular", observe the 404 Error Page again. [b]8)[/b] Return to an arbitrary public post to change the Comment Sort to "Oldest First". Then return to the thread you created to repeat steps 5 and 6, verifying that any attempt to change to or from Oldest First causes 404 Errors. [b]Result:[/b] A 404 Error Page is generated whenever I try to change the way Comments are Sorted in Private Threads. [b]Expected Result:[/b] Changing Comment Sort should not generate a 404 Error Page. [b]Notes:[/b] OS: Windows 7 Browser: Internet Explorer 10 Are you running add-ons/plug-ins?: None Dark/Light Theme: Dark Good luck webteam! I'm really looking forward to the next build of Bnext!