If you run custom Dexterity code that uses the MAPI_Send() function to attach a file in PDF format to an e-mail message, you experience one of the following symptoms:

  • The file attachment appears incorrectly as Winmail.dat instead of in the PDF format that you selected.

  • The file attachment appears to be missing even though it was attached to the e-mail message.


The Microsoft Exchange Server settings may cause the attachment to be sent in RTF format.

Client e-mail systems can receive e-mail messages that have an attachment. However, if the e-mail systems do not support RTF, the attachment cannot be separated correctly from the body of the message.


To resolve this issue, modify the Exchange Server settings.

For more information about Microsoft Exchange Server settings, click the following article numbers to view the articles in the Microsoft Knowledge Base:

841668 A mail-enabled contact may receive a Winmail.dat file attachment with an SMTP e-mail message instead of receiving the correct file attachment in Exchange 2000 Server

181953 Sending RTF with attachment as MIME loses attachment

821750 How to configure Internet e-mail message formats at the user and the domain levels in Exchange Server 2003

More Information

Steps to reproduce the issue

  1. Create a Dexterity customization by using the MAPI function library as described in the Dexterity Function Library Reference manual. Or, create the customization by using the MAPI dictionary.

    Note The MAPI dictionary is available as a download from Sample Applications for Dexterity on PartnerSource. To obtain the file, visit the appropriate PartnerSource Web site:

    Dexterity 10.0 9.0

  2. Send an e-mail message to a user who is outside your global access list.

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