DOCUMENT:Q149692  25-MAR-1999  [exchange]
TITLE   :XCLN: Error Message When Clients Try To Connect Via Internet
PRODUCT :Microsoft Exchange
PROD/VER:WINDOWS:4.0,5.0
OPER/SYS:
KEYWORDS:kbusage

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The information in this article applies to:

 - Microsoft Exchange MS-DOS client, versions 4.0, 5.0 
 - Microsoft Exchange Windows 3.x client, versions 4.0, 5.0 
 - Microsoft Exchange Windows 95/98 client, versions 4.0, 5.0 
 - Microsoft Exchange Windows NT client, versions 4.0, 5.0 
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SUMMARY
=======

When Microsoft Exchange clients try to connect to the Microsoft Exchange Server
over the Internet, the following error may be received.

   Microsoft Exchange could not be started. Network problems are preventing
   connection to the Microsoft Exchange Server computer. Contact your system
   administrator if this condition persists.

MORE INFORMATION
================

When it tries to connect to the Microsoft Exchange server over the Internet, the
Microsoft Exchange client needs to be able to get the IP address of the
Microsoft Exchange server from the Fully Qualified Domain Name (DNS Name) of the
Microsoft Exchange Server. This can be achieved through two ways:

 - The client has access to a DNS that is aware of the Microsoft Exchange
   Server.

 - The client computer has a local HOSTS file with an entry for the Microsoft
   Exchange Server computer.

In most cases, the client will have to have a local HOSTS file, since most DNS's
on the Internet will not have information about the Microsoft Exchange Server in
their tables.

NOTE: When creating a Microsoft Exchange profile on the client computer, it is
possible to enter an IP address as the Microsoft Exchange server name. The RPC
TCP/IP runtime routines know how to use a raw TCP/IP address to connect to the
server, but the DNS name is what gets stored in the profile. Hence, there must
be a DNS entry or local HOSTS file entry for the Microsoft Exchange Server in
order for the client to contact the server.

To verify that the client is able to communicate with the server, the following
tests could be run:

1. Ping the Microsoft Exchange Server name. This should tell us whether TCP/IP
   connectivity is available.

2. If you are able to "Ping" the server, use the RPC Ping utility to test RPC
   Connectivity with the server. This utility, present in the Microsoft Exchange
   Server CD in the Support\Rpcping directory, has two components, one to be run
   on the server and the other to be run on the client computer.

If there are problems with the RPC Connectivity, check to see if the server is
located behind a firewall. If a firewall is being used, it will need to
configured to allow access to the ports on the Microsoft Exchange Server that
are used by Microsoft Exchange. Please refer to the Microsoft Exchange Server
Release Notes for more information on "Setting TCP/IP Port Numbers for Internet
Firewalls"


Additional query words:

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Keywords          : kbusage 
Technology        : kbExchangeSearch kbExchange500 kbExchange400 kbExchangeClientSearch kbZNotKeyword kbZNotKeyword2 kbZNotKeyword3 kbExchange400DOS kbExchange500DOS kbExchange400NT kbExchange500NT kbExchange400Win95 kbExchange500Win95
Version           : WINDOWS:4.0,5.0

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