Understanding and Conquering Winmail.dat Attachments in Outlook

Updated On - December 16, 2023 by Henry Bray | Reading Time: 3 minutes

Summary: Are you looking forward to sending your data from MS Outlook to a non MS Outlook user? However, you must be aware of the fact that the recipient is likely to receive a Winmail.dat attachment. But there is nothing to worry about as here your solution is. We will discuss some manual methods and professional solutions that will help us to fix Winmail.dat attachments in MS Outlook.

MS Outlook is one of the most professional email clients that is being used by the business organizations to a great extent. It helps to manage our emails in a seamless manner which makes communication very easy. Have you ever wondered why MS Outlook, the most favored email client? It uses Rich Text Format that enhances the text and refines the attachments. However, it may pose a problem to non-MS Outlook users at times.

It isn’t necessary that you send an email from your MS Outlook account to another MS Outlook recipient. At times, your recipient can be a non-MS Outlook user as well. The experience of receiving emails to non-MS Outlook users is not as seamless as it is for the MS Outlook recipients. The users relying on a different email client often receive Winmail.dat attachment along with the email sent by the MS Outlook user. This file contains all the information of such text enhancements. This text enhancement is a feature which is only supported by Office 365 products such as MS Outlook, Gmail and MS Exchange. Hence, users receiving emails from an MS Outlook account are likely to receive this Winmail.dat attachment very often.

Now that we know about these types of attachments, let us discuss the common solutions to fix them.

Methods to Fix Winmail.dat attachments

It is an issue which requires elaborate solutions. One needs to make some changes in the settings. Here are different methods to fix Winmail.dat attachments.

Solution 1: Change the email format

Changing the email format can be helpful to avoid this issue. Usually the format supported by MS Outlook might not be supported by some other email client. There are two ways of changing the email format in MS Outlook.

Option 1: Change the format while sending the emails

This method is applicable only one or two people are facing this issue at a time. All you need to do is to draft your email in the usual manner and then before sending it, click on Format and then select Plain Text as the final format. Once done, send the email.

Option 2:  Change the default email format

Changing the default email format is important when a lot of people are facing this issue. Even when the number of receivers are more, you can prefer changing the default email format. This will change the default settings and you will not have to change the settings for every email you send. Here are the steps which are required for this.

  1. Open MS Outlook.
  2. Go to File and then select Options.
  3. As the window pops-up, go to the Mail category.
  4. Here locate Compose messages in this format. Steps to fix Winmail.dat attachments in Outlook
  5. In the drop-down beside it select Plain Text as the default email format. fix Winmail.dat attachments error
  6. Apply these changes to send your emails in Plain Text Format.

Solution 2: Prohibit selected users from receiving Winmail.dat attachments

Do you know that you can now prohibit selected users from receiving Winmail.dat attachments? Go ahead to know how.

  1. Open MS Outlook.
  2. Verify the recipients that should not be there in your contact book.
  3. Now compose an email and in the To section enter the recipient’s email address.
  4. Right-click on the email address you have entered and select Open Outlook Properties from the options.
  5. An Email Properties dialogue box will pop-up, there from the Internet format drop-down box select Send Plain Text.

Solution 3: Modify Registry Editor Settings

This is one of the toughest methods to avoid Winmail.dat attachments. That is why we never recommend you to try this method unless it is very important. Always seek the guidance of the person who knows this method. Else it will result in a number of complications. Here are the steps:

  1. Close MS Outlook.
  2. Press Win + R key to open the Run Window.
  3. In the Run window, type regedit and click on OK.
  4. Once done, navigate this path for Outlook 2016:
    HKEY_CURRENT_USER \ Software \ Microsoft \ Office \ 16.0 \ Outlook \ Preferences
  5. Once the Registry Editor is open, locate Preferences and make a right click.
  6. From the options list select New and then DWORD (32-BIT) Value.
  7. Now, name the DWORD as DisableTNEF and change the Value data to 1.

These methods might be complicated for the beginners. They are lengthy and time consuming too. Therefore, in such a situation, there is a need to look for some easy solutions. Here is a professional solution that will fix this issue instantly.

Regain Outlook PST Recovery Tool: One stop solution

Regain Outlook PST Recovery Tool is one of the finest Tool that can help you solve this problem. Sometimes despite following every method, you are not able to fix this issue. This happens because your PST files are corrupt. You can now recover your corrupt and damaged PST files with the help of this tool. This tool helps to retrieve the permanently deleted files as well. With the help of this automated solution, you recover your data without distorting it’s structure and format. It is very easy to execute this method.

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So, here we have taken note of almost every method so that the Winmail.dat attachment issue can be fixed. But, always remember to ensure that your files are not corrupt and if they are, repair them with Regain Outlook PST Recovery Tool. This will saves your time and efforts.


Author: Henry Bray

Henry Bray is a young technologist and content a Content Writer at Regain Software, loves to write about MS Outlook, MS Exchange Server, Office 365, Mozilla Thunderbird and many more email applications.

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