Admin Panel Problem

Helloo..I am having problems with my administartion panel..the problem is that whenever I try to edit something or whenever I click on other configurations ..it again comes back to the admnistarion panel home page..
For example if I click on Forum or style admin..it redirects it self to the admin panel homepage no matter how many time I click..and shows the same "Welcome to Administration" page and it makes me unable to make any settings or to do any editings..

So if u have any solution to dis problem ..den plzz tell me..