XADM: Encrypted Message Unreadable When TNEF Is Turned On

ID: Q189268

The information in this article applies to:

Microsoft Exchange Server, versions 5.0, 5.5

SYMPTOMS

Encrypted messages sent to a transport-neutral encapsulation format (TNEF) recipient arrive as attachments and are unreadable if Internet Mail (IMAIL) is configured for TNEF.

CAUSE

This problem resulted when S/MIME encrypted messages were being sent as TNEF attachments when sent to a TNEF recipient, resulting in the received message being unreadable. TNEF has subsequently been disabled on outbound for encrypted messages.

STATUS

Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 5.0.

A supported fix is now available, but has not been fully regression-tested and should be applied only to systems experiencing this specific problem. Unless you are severely impacted by this specific problem, Microsoft recommends that you wait for the next service pack that contains this fix. Contact Microsoft Technical Support for more information.

This fix has been posted to the following Internet location:

ftp://ftp.microsoft.com/bussys/exchange/exchange-public/fixes/Eng/Exchg5.0/Post-SP2-STORE/

Microsoft has confirmed this to be a problem in Microsoft Exchange Server version 5.5. This problem has been corrected in the latest U.S. service pack for Microsoft Exchange Server version 5.5. 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 : XADM
Version : WINDOWS:5.0,5.5
Platform : WINDOWS
Issue type : kbbug