Firewall Problems - Cannot play Diablo II

A few months ago, I started playing Diablo II online. Everything was fine until recently, it freezes when I sign on and it goes to the "Checking Versions" window to see if I have the latest patch. I have the latest patch, but it keeps scanning, and NEVER stops! I have contacted blizzard and they said it must be something with my firewalls, but I dont see how it could be since I added the ports Diablo II runs on, and just now had problems.

What could be causing this? I thought I allowed my firewalls to let Diablo II play online!

 

Game

Another thing to consider you might look at rules if it set to high for games it won't allow you to do so, do you have administration privilage !? is your domain administrator has restrict installation , it will also cause same problem.