Do you have any firewall/router or something that might block connections or even p2p things.If you have try to disable it and try again
I had this problem sometimes with my old internet so I thought its slow internet connection (but now I think its stupid idea ). But my problem is different it happen (rarely) after game when I go back into channel. Btw I have new intenet connection and sometimes it happens so I rejoin and after that it works fine for me
Try re-running eurobattle.reg if that doesn't works try doing eb installer (as niceone said ) again if that doesn't work try re-installing warcraft 3
someone give him the reg reset file.
You all ready got it in your folder eurobattle.reg