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Open a .msg or winmail.dat File Without Outlook SATCHEL

Read the email inside an Outlook .msg or a winmail.dat, save its attachments, and turn it into an .eml any mail program opens. It is all read in this tab.

The file

Drop a .msg or a winmail.dat here, or choose one

What these two files are

A .msg is what Outlook writes when an email is dragged out of it onto the desktop, or attached to another email. It is not text: it is the same kind of container as an old Word .doc, a small file system with the message's properties stored as separate streams inside it, and another whole .msg inside any attachment that is itself an email. Only Outlook opens one, which is a problem for anybody on a Mac, a phone, Gmail or Thunderbird who has been sent one.

winmail.dat arrives instead of the attachments you were expecting, when the sender's Outlook used its own rich-text format for a recipient that does not understand it. The real attachments, and usually the formatted body, are packed inside it. Nothing is wrong with the email; it just needs unpacking.

Why not an upload site

The usual answer to both is a website that converts the file on its server. That is the whole email, its attachments, the names and addresses of everyone on it, and very often the full internet headers that record which servers and addresses it passed through, handed to a company you know nothing about. SATCHEL reads both formats in this tab. The compressed rich text Outlook often stores the body in is decompressed here too, and when it is Outlook's wrapping of an HTML email the original HTML is recovered.

What it shows, and what it does not do

  • The message, with sender, recipients, dates and the body as it was formatted. Pictures sent inside the email are shown; pictures on the internet are not fetched, because a picture loading is how a sender learns an email was opened.
  • Every attachment, each one savable, and an email attached to the email opened in place.
  • An .eml of the whole thing, with the attachments, which Apple Mail, Thunderbird, Gmail's importers and Outlook itself all open. When the .msg kept the headers it arrived with, the .eml keeps them too.
  • A warning on attachments that run code when opened, on a program dressed up with a document's name, and on a file that fails its own checksums.

It does not open encrypted or signed Outlook messages (S/MIME), which need the recipient's key, and it does not run anything in the email. To check where an email really came from, copy its headers into HEADERPROOF, or open the .eml in MAILBOX. For a link in it you are unsure of, PHISHLENS reads it without visiting it.

Questions people ask about SATCHEL
How do I open a .msg file without Outlook?

Drop it on this page. SATCHEL reads the Outlook message format in your browser and shows the email with its sender, recipients, dates, formatted body and attachments. Nothing is uploaded, so it works for a confidential email too.

What is winmail.dat and how do I get the attachments out?

It is the file Outlook sends when it uses its own rich-text format for a recipient whose mail program does not understand it. The real attachments and the formatted body are packed inside. Drop it here and each attachment can be saved on its own.

Can it convert .msg to .eml?

Yes. Save it as an .eml and you get an ordinary email file with the body and every attachment, which Apple Mail, Thunderbird and Outlook all open. When the .msg kept the internet headers it arrived with, the .eml keeps them too.

Are the attachments uploaded anywhere?

No. The file is read by the browser and taken apart in the tab. The attachments are saved straight from memory to your computer.

Why are some pictures missing from the email?

Pictures that were sent inside the email are shown. Pictures that live on the internet are not fetched, because loading one tells the sender, and whoever runs the server, that the email was opened, when, and roughly where. That is how tracking pixels work.

Can it open an encrypted Outlook message?

No. An S/MIME encrypted message can only be opened with the recipient's private key, which belongs in their mail program. SATCHEL says so rather than guessing.

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