Technology Notebook

Exchange 2000 Static Port Mapping

http://support.microsoft.com/support/kb/articles/q270/8/36.asp

If you're using Microsoft Exchange 2000 Server, you might be wondering why you cannot connect to the server over the Internet with an Exchange-capable mail client such as Outlook. When an initial connection is made from Outlook to the Exchange server, port 135 is used to establish the session. After that, further communications occur over two randomly selected ports - one for the Information Store and one for the Directory. The problem is that firewalls will block activity on these other ports unless you specifically allow traffic to pass on them. Being that the ports are randomly selected, this obviously makes it fairly difficult. A couple of registry hacks later, and you can force Exchange to use static ports for these sessions, which can then easily be allowed to pass through a firewall.


Exchange Server 5.5 Static Port Mapping

http://support.microsoft.com/support/kb/articles/Q155/8/31.asp

Exchange 5.5 basically works the same way, but it is slightly different, so I decided to toss this one in as well to be sure you have the right set of instructions for your particular server version.


TCP/UDP Ports Used By Exchange 2000 Server

http://support.microsoft.com/support/kb/articles/q278/3/39.asp

So, we've learned that Exchange can be setup to perform certain communications over specifically assigned ports, but you might be left wondering what other TCP/UDP ports that Exchange is chattering with on the network. This is particularly useful information for those of you that need to make allowances for additional Exchange capabilities in your firewall configuration.