This is an archive of a Blizzard Support post on the proper port settings and link to help with proxies and Battle.net http://forums.battle.net/opensupport/posts/yh/24542.shtml Subject: Definitive Fix for many battle.net crashes From: EdwardH Date: Fri Jul 5 16:41:24 On Fri Jul 5 15:35:20, AegisZero wrote: > I was having many problems with crashing in battle.net, until I > read an earlier post and messed around with firewall settings. If other people are having crashes upon entering battlenet, it could be because your firewall is blocking the port that is being used by war3. To resolve this, either open up port 6112 using your advanced settings for your firewall, or as in my case if you have free zonealarm, just shut it down when you play. > I hope this helps ya'll out, and Blizzard, you might want to add > to the blurb on your tech support website about trying to shut down > the firewall before playing on bnet, because I figure that a lot of > people are having the same port being blocked by their free > firewall (ie zonealarm) Blizzard does not support proxies (Internet connection sharing), firewalls, or routers. The settings provided are suggested settings only. You may need to contact your ISP or network administrator for assistance if you have opened the correct ports but still cannot connect or get others connected to you. Here are some common questions and answers regarding proxies, firewalls, and routers. What do I need to know about ports? Anytime your computer receives incoming data, it is sent to a "port". Your computer has many ports that can receive data, and different activities will utilize different ports. How are ports restricted when using a proxy, firewall, or router? Most proxy servers, firewalls, and other Internet connection sharing methods can restrict port access. Your configuration may be restricting packets from "unknown sources". In this case an "unknown source" would be defined as any IP address that you have not initiated the contact with. Once you contact the IP address, your proxy and/or firewall considers it "safe", or a "known source", since you initiated the contact. When you create a game on Battle.net, other users need to be able to contact you in order to join. In other words, they need to be able to initiate the contact. This becomes the real problem if your connection is restricting them from contacting you. What ports need to be open? In order to connect to Battle.net and allow others to connect to you, using any Blizzard Entertainment game, the following ports need to be opened: 4000 UDP 4000 TCP 6112 up to 6119 UDP 6112 up to 6119 TCP Some firewall programs have preset ports available in their configurations that are often necessary to be open. One in particular is a connection to your DNS server. This usually takes place on UDP port 53. Please go to this link for more information on how to open the appropriate ports for your proxy or firewall: http://www.blizzard.com/support/?id=mdt0243p What do I do if I am still having problems connecting using a firewall, router, or proxy? If you need further help configuring your firewall, router, or proxy you will need to contact the manufacturer for assistance. --Edward H.