Exchange Server 2007 does not have Transport Neutral Encapsulation Format (TNEF) capabilities for POP and IMAP protocols

If you use Microsoft Outlook clients to connect to Microsoft Exchange Server 2007 mailboxes by using POP3 or IMAP4 protocols, Outlook clients may be unable to use the following features:

• The formatted text version of the message. For example, font information and colors cannot be used.
• OLE objects. For example, embedded pictures and embedded Microsoft Office documents cannot be used.
• Special Outlook features. For example, custom forms, voting buttons, and meeting requests cannot be used.
• Regular file attachments that were added to the original message cannot be used.

This problem occurs because Exchange Server 2007 does not support Transport Neutral Encapsulation Format (TNEF) for POP3 or IMAP4 protocols.

Update information

To resolve this problem, install Update Rollup 2 for Exchange 2007 Service Pack 1. For more information about Update Rollup 2 for Exchange 2007 Service Pack 1, click the following article number to view the article in the Microsoft Knowledge Base:

After you apply this hotfix on the Exchange Server 2007 server, the following cmdlets can be used to set the message format to TNEF.

Server-based cmdletUser-based cmdletA restart of the Exchange Services or a restart may be required for changes to take eaffect. Enabling this setting may cause HTML and Rich Text Formatting to be lost when messages are retrieved by using IMAP or POP.

Transport Neutral Encapsulation Format (TNEF) is a Microsoft proprietary method for encoding Rich Text Format (RTF) messages that are sent across the Internet. A TNEF-encoded message contains a plain text version of the message, an attachment that contains the RTF version, and any OLE objects such as pictures or other attachments that were sent with the message.