XCLN: How to Connect over the Internet to an Exchange Server (152725)

SUMMARY

Microsoft Exchange clients can connect to Microsoft Exchange Servers over the Internet via third party Internet Service Providers.

In order to connect from a client, you must:

Have dial-in or direct connection to the Internet.
Be validated by the Microsoft Exchange Server's NT domain in order to talk to Microsoft Exchange Server via RPCs. To verify this, clear the Use Network Security During Logon checkbox. This will require domain login credentials when you start the Microsoft Exchange client with this profile.
Put the Microsoft Exchange Server name in the client's HOSTS file with IP address.
Have the ability to ping the Microsoft Exchange Server by server name

MORE INFORMATION

Connecting Microsoft Exchange clients to Microsoft Exchange Servers over the Internet is similar to using a large WAN. When a client communicates with an Exchange Server over the Internet, the TCP/IP packets are sent across several routers along the way. This route may not always be the same. Also, in order for an Outlook client to establish proper communication with an Exchange Server, it needs to use TCP/IP port 135. This means that TCP/IP port 135 has to be enabled on all routers (and firewalls) in a packet's path for RPC communication to work. This condition cannot always be ensured because several routers on the Internet disable TCP/IP port 135. Use RPCPing.exe on both the server and client computers to verify that RPC communication is working. For additional information about the RPCPing utility, click the article number below to view the article in the Microsoft Knowledge Base:

167260 XCLN: How to Use RPCPing to Test RPC Communication