KF KF w/o router connection problems.

Hello, i have a big problem with KF connection.

I can connect to servers in Server Browser, but no one can connect to me, if i create listen server. My friends can't connect to me via Steam "Join" menu in Steam overlay. They can't connect to me, even directly entering IP in console or Server Browser.

Now the main facts:

I am using Steam version.

I used router, but when i thought, that problem in router, i have connect my internet cable directly into computer.

I have DISABLED FIREWALL at all (but just in case i created rules for KF ports).

I have disabled Anti-virus program fully (Avast).

I have no file, named Steam_appID.ini, and never had it.

I tried to set ServerBehindNAT to TRUE and [UPNP] Enabled to FALSE, and tried vice versa.

My friends tried to connect me, via Steam overlay and Via directly typing my IP in server browser.

So. None of things i read before helped me. And i am in despair. Please, tell me, what am i doing wrong and how to make proper server, that other people can connect?

Excuse my English.