How e-mail message formats affect Internet e-mail messages in Outlook

• The formatted text version of the message (for example, font information and colors).
• OLE objects (for example, embedded pictures and embedded Microsoft Office documents).
• Special Outlook features (for example, custom forms, voting buttons, and meeting requests).
• Regular file attachments that were added to the original message.

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Sending and Receiving Concerns

• The plain text version of the message is received and it contains an attachment named Winmail.dat. The Winmail.dat attachment does not contain any useful information when you open it because it is in the special TNEF format.
  
  Note Some users have reported receiving a Win.dat attachment.
• The plain text version of the message is received and it contains an attachment with a generic name such as ATT00008.dat or ATT00005.eml. In this case, the client is unable to recognize the TNEF part of the message, but is unable to recognize the Winmail.dat file name, so it creates a file name to hold the TNEF information.
• The plain text version of the message is received and the client ignores the Winmail.dat attachment. This is the behavior found in Microsoft Outlook Express. Outlook Express does not understand TNEF, but it does know to ignore TNEF information. The result is a plain text message.

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Message Encoding

   ------ =_NextPart_000_01BA6275.348C1000
   Content-Type: application/ms-tnef
   Content-Transfer-Encoding: base64
 
   eJ8+IisSAQaQCAAEAAAAAAABAAEAAQeQBgAIAAAA5AQAAAAAAADoAAENgAQAAgAAAAEAAQ
   ABBJAGAEgBAAABAAAADAAAAAMAADACAAAACwAPDgAAAAACAf8PAQAAAHQAAAAAAAAAtTvC
   [. . .]

					

   begin 600 WINMAIL.DAT
   M>)\^(C<.`0:0" `$```````!``$``0>0!@`(````Y 0```````#H``$%@ ,`
   M#@```,L'" `$``<`)P`O``4`0 $!"8 !`"$````S,S5$,C,W,#%"0T-#13$
   [. . .]

					

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How to Control TNEF in Messages

• Global - If you change your default e-mail format to plain text or Hypertext Markup Language (HTML), it helps to ensure that TNEF is not sent unless an Outlook feature needs it.
• Per Recipient - You can specify in the recipient's e-mail address to not send TNEF so that a recipient always receives plain text versions of the message.
• Per Message - When you compose a new message, or replying to a received message.

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Method 1: How to specify e-mail format in Microsoft Office Outlook 2007

Global Change

1. On the Tools menu, click Options.
2. Click the Mail Format tab.
3. In the Compose in this message format box, click Plain Text or HTML, and then click OK.

1. On the Tools menu, click Options, and then click the Mail Format tab.
2. In the Compose in this message format box, click Rich Text, and then click OK.

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Method 2: How to specify e-mail format in Microsoft Office Outlook 2003 and earlier versions of Outlook

Global Change

1. On the Tools menu, click Options, and then click the Mail Format tab.
2. In the Send in this message format box, click Plain Text or HTML, and then click OK.

1. On the Tools menu, click Options, and then click the Mail Format tab.
2. In the Send in this message format box, click to select Microsoft Outlook Rich Text Format, and then click OK.

Per Recipient Change

1. Open the recipient's record in the Contacts folder.
2. Double-click the recipient's e-mail address.
3. Choose Send Plain Text only in the Internet Format box.

1. Open the recipient's record in the Contacts folder.
2. Double-click the recipient's e-mail address.
3. Click Send Using Outlook Rich Text Format in the Internet Format box.

1. Locate the recipient in the Personal Address Book.
2. Double-click the recipient's e-mail address.
3. Click to clear the Always send to this recipient in Microsoft Exchange Rich Text Format check box, and then click OK.

1. Locate the recipient in the Personal Address Book.
2. Double-click the recipient's e-mail address.
3. Click to select the Always send to this recipient in Microsoft Exchange Rich Text Format check box, and then click OK.

Method 1: Per message change in Outlook 2007

1. Open a new mail message, or click Reply on a received message.
2. On the Options tab, click HTML or Plain Text.

1. Open a new mail message, or click Reply on a received message.
2. On the Options tab, click Rich Text.

Method 2: Per message change in Outlook 2003 and earlier versions of Outlook

1. Open a New mail message, or click Reply on a recently received message.
2. On the Mail Format toolbar, click to select Plain Text or HTML from the dropdown menu.

1. Open a New mail message, or click Reply on a recently received message.
2. On the Mail Format toolbar, click to select Rich Text from the dropdown menu.

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Common Scenarios

• Problem: Recipient receives the Winmail.dat attachment.
  Solution: Turn TNEF off (either for the recipient, or globally).
  
  
• Problem: Recipient receives the ATT00001.DAT attachment.
  Solution: Turn TNEF off (either for the recipient, or globally).
  
  
• Problem: Recipient does not receive regular file attachments.
  Solution: Turn TNEF off (either for the recipient, or globally).
  
  
• Problem: Recipient does not have Voting buttons in Outlook.
  Solution: Turn TNEF on for the recipient.
  
  
• Problem: Recipient receives meeting requests as regular messages.
  Solution: Turn TNEF on for the recipient.
  
  
• Problem: Recipient does not receive custom form information.
  Solution: Turn TNEF on for the recipient.
  
  
• Problem: Recipient does not receive formatted message text.
  Solution: Turn TNEF on for the recipient.

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