Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17



Posted on 1999-06-23
Medium Priority
Last Modified: 2013-11-18
I get mail that has an attachment that is "application/ms-tnef" mime type. I cant open any attachments
that this person sends me. Netscape cant find a plugin. Can you help.
Question by:jayru
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
LVL 19

Expert Comment

by:Serena Hsi
ID: 1625092
What is the format of these files the person is sending you?  When you right-click and save-as, what is the file extension?

Accepted Solution

reddarin earned 200 total points
ID: 1625093
The fix will require the person sending you email to change the way Outlook is sending it. There is nothing you can do on your end short of installing and using Outlook as your email client rather than Netscape.

Although this KB article is long winded, the fix is fairly straight forward.


OL98: Attachments Not Visible to Some Recipients When Using TNEF
The information in this article applies to:
Microsoft Outlook 98

Using Microsoft Outlook 98 you have enabled Transport Neutral Encapsulation Format (TNEF) to guard against information loss when sending mail. Because of this setting, recipients who do not use Outlook report that attachments do not display in mail they receive from you.

When TNEF is enabled, attachments are handled by this format. The Internet standards for encoding and attaching files such as Multipart Internet Mail Extensions (MIME) and UUENCODE are not invoked while TNEF is active, therefore e-mail clients that do not read TNEF in the message do not receive an attachment.

Enable TNEF only for recipients who are using Outlook or e-mail clients that are capable of interpreting TNEF. The Microsoft Outlook Rich Text Format enables TNEF for messaging in Outlook.


Internet Mail Only Installation (IMO)
To enable TNEF using RTF in each mail message that will contain Outlook items as attachments, follow these steps:
1. On the File menu click New and then Mail Message.

2. On the File menu of the blank message, click Properties. Click "Send in

   Microsoft Outlook Rich Text Format."

3. On the Insert menu, click Items and then select the items you wish to
   include as attachments.

To enable TNEF in Outlook globally, follow these steps:
1. On the Tools menu click Options and then click the Mail Format tab.

2. In Send In This Message Format, click Microsoft Outlook Rich Text


Corporate or Workgroup (CW)
Sending using Microsoft Exchange, Rich Text Format may be enabled globally or per recipient. The global procedure is the same as outlined for IMO installations above. To enable Exchange Rich Text Format per recipient, using either the Personal Address Book or Outlook Address book to create a mail message, follow these steps:

1. On the File menu, point to New and click Mail Message. In the message,

   click to select an address from the list and click To.

2. Right click the address and click "Add to Personal Address Book."
   Right click the address a second time, click Properties and then click
   "Always send messages in Microsoft Exchange rich text format.

3. Send the mail message by clicking Send.
TNEF is helpful when sending Outlook items such as Contacts and Mail messages and other form based items. When not sending these items, TNEF should be disabled. In order to ensure that all users get file attachments as MIME items as expected set the mail format to Plain Text or HTML.


Rich Text Format (RTF)
RTF is a document type/message type that is used to define both the content of a message and how that message should look (with bold, colored fonts, etc). It was created by Microsoft to provide richly formatted messages before HTML was readily available for use with mail

Transport Neutral Encoding Format (TNEF)
TNEF is a method used to encode RTF so that it can be sent safely over the internet without losing data. TNEF is only used to encode RTF message types. This includes contacts, meeting requests, messages with voting buttons, etc. If an RTF message is not encoded before it is sent to the Internet, it will be converted to plain text. Most mail clients do not understand TNEF (or RTF for that matter). If a mail client receives TNEF that it doesn't understand, it will display a plain text version of the original message with an attachment called "winmail.dat" that can't be opened.

For more information on Transport Neutral Encapsulation Format (TNEF), please see the following articles in the Microsoft Knowledge Base:

   ARTICLE-ID: Q185997
   TITLE     : (IMO) TNEF Information Not Retained Sending HTML E-mail

   ARTICLE-ID: Q186021
   TITLE     : (CW) HTML Attributes Not Retained When Sending to MSN

   ARTICLE-ID: Q186232
   TITLE     : (CW) CC:Mail Does Not Preserve HTML Format

Additional query words:
Keywords          : MsgRead
Version           : WINDOWS:
Platform          : WINDOWS
Issue type        : kbbug
Solution Type     : kbpending

Last Reviewed: June 2, 1999

Author Comment

ID: 1625094
Thanks for the help. I didn't realize it was an outlook vs netscape mail thing. I can open anything the person send to me at work because I use Outlook at work. Thanks again.

Featured Post

Free Tool: Site Down Detector

Helpful to verify reports of your own downtime, or to double check a downed website you are trying to access.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

In this step by step procedure, you will come to know the details of creating an Outlook meeting in 2007, 2010, 2013 & 2016.
This article describes how to import Lotus Notes Contacts into Outlook 2016, 2013, 2010 and 2007 etc. with a few manual steps. You can easily export and migrate Lotus Notes contacts into Microsoft Outlook without having to use any third party tools.
Get people started with the process of using Access VBA to control Outlook using automation, Microsoft Access can control other applications. An example is the ability to programmatically talk to Microsoft Outlook. Using automation, an Access applic…
Many of my clients call in with monstrous Gmail overloading issues with Outlook. A quick tip is to turn off the All Mail and Important folders from synching. Here is a quick video I made to show you how to turn off these and other folders in Gmail s…

670 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question