EML Tools

Open a winmail.dat file

This winmail.dat reader opens the message inside a winmail.dat attachment and lets you download the files Outlook packed into it. Drop the file on the box to start.

Runs in your browser. Your files never leave your device.

How to use it

  1. Save the winmail.dat attachment from your email, then choose it here. You can also drop the whole email as an .eml or .msg file.
  2. Read the message. The files that were inside winmail.dat are listed below it.
  3. Download each file, or all of them at once as a ZIP.

What is winmail.dat?

When Outlook sends an email in its own rich text format, it packs the formatting and the attachments into a single file called winmail.dat, in a Microsoft format named TNEF. Outlook on the other end unpacks it without anyone noticing.

Apple Mail, Gmail, phones and most other mail apps don't understand TNEF. Instead of the PDF or photo that was sent, you see one attachment called winmail.dat that nothing seems to open. The files are all still in there, and this page takes them out.

How to stop receiving winmail.dat

Ask the sender to send in HTML or plain text. In Outlook that's File > Options > Mail > “Compose messages in this format”. If one contact's emails keep arriving as winmail.dat, the sender can open that contact and set its internet format to “Send plain text only”.

If the whole organisation sends them, the Exchange administrator can turn TNEF off for outgoing mail with Set-RemoteDomain Default -TNEFEnabled $false.

FAQ

Is my winmail.dat file uploaded?

No. Most winmail.dat openers upload the file to their server; this one unpacks it in your browser, so the attachments never leave your device.

How do I open winmail.dat on an iPhone?

In Mail, press and hold the winmail.dat attachment and choose Save to Files. Then open this page in Safari, tap the box and pick the file from Files.

Do I need to install a winmail.dat opener on Windows?

No. This page opens winmail.dat files in any current browser on Windows, so there is no program to download.

Can I open winmail.dat on a Mac?

Yes. Save the attachment from Apple Mail, then drop it on the box in Safari or Chrome. No app to install.

The message is empty. Is something missing?

Some winmail.dat files only hold the attachments and the formatting, while the text stays in the email itself. The files you were sent are listed either way.

Do the other tools handle winmail.dat?

Yes. When an .eml or .msg file has a winmail.dat attachment, the viewers and converters on this site unpack it automatically and show the files inside.

Other tools