Microsoft KB Archive/157695

= XFOR: MTA can't Communicate with Another MTA via French X.25 =

Article ID: 157695

Article Last Modified on 10/28/2006

-

APPLIES TO


 * Microsoft Exchange Server 4.0 Standard Edition

-



This article was previously published under Q157695



SYMPTOMS
If Microsoft Exchange is configured to use a sub address, it can't communicate with another Microsoft Exchange Message Transfer Agent (MTA) or any other MTA through the French X.25 network (Transpac). When Microsoft Exchange accepts an X.25 call, it sends back a Call Accept packet with its own X.121 address.



CAUSE
The CCITT X.25 1988 recommendations state that there are two formats for this packet: Basic and Extended. If the Extended format is used, an Address block is optional and Microsoft Exchange will operate successfully. However, the French X.25 network uses the Basic format. The problem occurs since the French X.25 network automatically adds the local DTE address. The only time that this problem occurs is when you use a sub address.



MORE INFORMATION
Microsoft Exchange fails to communicate over X.25 in France. The Extended format is only used if a specific complementary service is required. The Address block is only used if Call Forwarding is active. Since this service is not requested and the Address block is non zero, the X.25 network clears the communication with an error code of 4A which translates into Longer of Address non zero.



STATUS
Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 4.0. This problem was corrected in the latest Microsoft Exchange Service Pack. For information on obtaining the Service Pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K

Keywords: kbnetwork kbusage KB157695

-

[mailto:TECHNET@MICROSOFT.COM Send feedback to Microsoft]

© Microsoft Corporation. All rights reserved.