Article ID: 197064 - View products that this article applies to.
For a Microsoft Outlook 2000 (IMO) version of this article, see 196784
For a Microsoft Outlook 98 (IMO) version of this article, see 193117
For a Microsoft Outlook 98 (CW) version of this article, see 193118
NOTE: These procedures only apply if you have installed Outlook with the Corporate Workgroup/Other option. This option allows you to use Messaging Application Programming Interface (MAPI) services. To determine your installation type, on the Help Menu click About Microsoft Outlook. In About Microsoft Outlook you should see "Corporate" if you have the Corporate Workgroup installation.
When you use Microsoft Outlook to send e-mail containing attachments through the Internet, some recipients using e-mail clients, other than Outlook, report that the mail message includes an additional file called Winmail.dat. The file is usually very small, but cannot be opened in the mail message.
The Winmail.dat file is used to preserve formatting that the sending client includes in the message, but is not recognized by the receiving client. In the case of Outlook, the Winmail.dat file includes Rich Text Formatting (RTF) instructions. This type of formatting is used with the Microsoft Outlook Rich Text Format and when using Microsoft Word as an e-mail editor.
To avoid including Winmail.dat, use the Plain Text mail format. To select Plain Text for all messages, follow these steps:
To set Plain Text by recipient in the Address Book, follow these steps:
For additional information on Winmail.dat attachments, click the article numbers below to view the articles in the Microsoft Knowledge Base:
(https://support.microsoft.com/kb/149203/EN-US/ )XFOR: Preventing Winmail.dat From Being Sent Over IMC
(https://support.microsoft.com/kb/138053/EN-US/ )XFOR: Preventing WINMAIL.DAT Sent to Internet Users
(http://go.microsoft.com/fwlink/?LinkId=151500)for other considerations.
Article ID: 197064 - Last Review: June 22, 2014 - Revision: 2.0