Depends on what services you need to expose outside of that location or network. Checkout this <a href=”http://support.microsoft.com/kb/270836″>MS KB Article on static port mappings for Exchange</a>. This <a href=”http://mymcp.blogspot.com/2007/06/microsoft-exchange-tcpip-ports-list.html”>MCP blog posting</a> may also help. Let us know what you are trying to accomplish across the firewall and we will be glad to further assist.
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