XFOR: Lotus Notes SMTP Users Receive .unk Files (259065)

SYMPTOMS

When you send an e-mail message to a Lotus Notes domain by using the Internet Mail Service (not the Microsoft Exchange Connector for Lotus Notes) the Lotus Notes recipient may receive a message that contains an attachment named either Att1.unk or C.dtf.

CAUSE

This issue can occur if you sent the message as Microsoft Rich Text. The Lotus Notes message transfer agent (MTA) may not correctly read the format of the message or attachment.

RESOLUTION

To resolve this issue:

On the Internet Mail tab in the properties of the Internet Mail Service, click Advanced Options, and then change the Rich Text option to User. -or-
On the Internet Mail tab in the properties of the Internet Mail Service, click Email Domains, create an entry for the Notes domain (SMTP domain), and then select the option to never send Microsoft Rich Text to that domain.

MORE INFORMATION

More information about which versions of the Lotus Notes SMTP MTA experience this issue can be found in a Lotus Customer Support Technote, number 145368, titled Text Attachments Appear as .UNK Files after Passing Through the SMTP MTA. This Technote is available from the following Lotus Web site:

http://www-306.ibm.com/software/lotus/

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