Mail from Outlook 97 contains a Winmail.dat file attachment or an Att000xx.dat file attachment in Outlook 2000 (259037)


The information in this article applies to:

  • Microsoft Outlook 2000
This article was previously published under Q259037

SYMPTOMS

When you use Microsoft Outlook 2000 to read an e-mail message that was sent from Outlook 97 using the Internet Mail service, if the e-mail message contains Transport Neutral Encapsulation Format (TNEF) information, Outlook 2000 shows the TNEF information as either a Winmail.dat file attachment or an Att000xx.dat file attachment, where "xx" is a number specific to your computer.

CAUSE

Outlook 2000 expects that messages containing TNEF formatting have a TNEF Correlator field in the header of the message. This field tells Outlook 2000 to expect the TNEF data and to convert the TNEF data to an appropriate format in the message. Outlook 97 does not write the TNEF Correlator field into the message header, so Outlook 2000 does not convert the data.

Outlook 98 does not require the TNEF Correlator field, so messages sent from Outlook 97 to Outlook 98 are converted as expected. Additionally, Outlook 98 does include the TNEF Correlator field with mail that you send, so messages sent from Outlook 98 to Outlook 2000 are converted correctly.

WORKAROUND

To work around this behavior, you must send the message in the plain text format.

To send ONE message as plain text:
  1. On the Actions menu, point to New mail Message Using, and then click Plain Text.
  2. In the To box, type a valid e-mail address, such as "someone@microsoft.com."
  3. Right-click the e-mail address, and then click Properties.
  4. Make sure that the Always send to this recipient in Microsoft Outlook rich-text format check box is not selected, and then click OK.
  5. Click Send to send the message.
To send ALL messages to a contact as plain text:
  1. Open a contact you want to send messages to as plain text.
  2. In the E-mail box, double-click the e-mail address.
  3. Clear the Always send to this recipient in Windows Messaging rich-text format check box.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

For additional information about TNEF, click the article number below to view the article in the Microsoft Knowledge Base:

241538 OL2000: How Message Formats Affect Internet Mail

Modification Type:MajorLast Reviewed:12/2/2004
Keywords:kbbug kbnofix KB259037
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