bbpress menu tree problem

Hi!

I have problem with bbpress forum link tree.  

you can see in first screenshot “Geoteknik Anabilim Dalı” forum.

First screenshot: http://yadi.sk/d/laNGEJsbLj5VM

Everything is ok in first one.

But,

For example in  “Geoteknik Anabilim Dalı” forum click “link tree” below the main menu, you get  an error “404 not found”.(2. And 3. Screenshot)

Second screenshot: http://yadi.sk/d/eEhwnOBtLj5gW

Third screenshot: http://yadi.sk/d/cL0xcyMtLj5i4

And problems continue..

in topics, i have similar problem like this problem.

For example; check first screenshot please:

http://yadi.sk/d/RycNDvXbLj9h3

and then second screenshot

http://yadi.sk/d/dRj1XrgeLj9jX

How can i fix these problems?  

Regards..