I had this problem almost constantly in Arma 2 OA where I could not gather any servers via the browser. I was pleased to find that in Arma 3 the problem seemed to be non-existant however, for some reason after constant playing of the game; today it stopped working. I cannot join any servers remotely or through the server browser. Nothing has changed with ports or my internet since yesterday but no matter what I do the problem seems to persist now. I've done the obvious and made sure my filter settings are set correctly and that my LAN option is not checked on, I've also restarted steam, verified the game cache, restarted my computer, and restarted steam. Not sure what else to do as nothing seems to be working =(.
