Can't connect to servers

So, I can't connect to any servers.

I bought ArmA2:CO from sprocket and downloaded and installed both, first ARMA2 and then Operation arrowhead. Then updated the OA to 1.54. Here's the first problem: the updater didn't update arma to 1.07 atomatically.

I tried and tried manually with different updaters, no success, so I reinstalled ArmA2 cause the error said that install may be corrupt.

Same problem came and the error message was the same, something like "you haven't installed the game or setup is corrupt".

Then i google'd and found out a solution:

I needed to edit my registry and add a string value to "HKEY_LOCAL_MACHINE\SOFTWARE\Bohemia interactive studios\ArmA 2" called "MAIN" and the value data was the path to main arma2 folder. This way the patch started working and now ARMA2 and OA are both updated with latest patches.

I've only been able to connect to one OA server (same problem in both arma and OA) and that was when it was empty. When there were players I only got stuck to "waiting for host". Some times it said that I was connected and was able to chat to players inside the server, but still "waiting for host".

And when I tried to connect (while players inside) I took the servers desync to skies.

And it seems that the OA somehow clogs up my internet connection! When I were alone in the server, after a while, my connection to TeamSpeak was terminated. And when there were players in the server (and TS) the TS works fine if im not doing anything, but when I tried to connect to server, the TS started lagging and eventually it terminated my connection!

And if I try to join any other server (populated or not) I get "connection failed" after a while. Sometimes Just stuck to waiting for host.

Arma2, OA and TS are all exceptions in my firewall!

My singleplayer works fine. And I've played OFP before with the same group. What might be causing this??

And apologies for my english, I'm only Finnish!

This sounds odd, did you install OA into the Arma 2 folder or did you specify a different path on install?

What is your average ping when trying to connect to servers?

Are you sat behind an adaptive firewall?

Yea, the problem seemed to be my modems firewall, all works now!