Problem with Buddypress

Hello people. I have a problem that i can not solve.
I am using WP 3.4.2 + bbPress 2.1.2 and i recenlty installed BuddyPress. But here comes the problem every buddypress page (for ex. Log in, Log out, Messages, Profile and so on) is blank. Just opens a blank page and nothing happen. How can i fix this? I tried both versions – the newest one and older one 1.6.1.

I read a lot of info in the net but nothing helped me. I hope you can give me some directions to fix this annoying problem.