EML File: Read Email and Inspect Message Source

Quick facts

Extension

.eml

Format

Email Message

Category

document

MIME type

message/rfc822

Standard / developer

IETF

Open with

Outlook (new)

What is EML?

An Internet message has header fields, such as sender and subject information, followed by an optional body separated by an empty line. MIME can represent multipart bodies and different content types. An EML is a saved message, rather than a complete mailbox or a standalone attachment.

How to open EML

Reading the message, following links and opening attachments are separate actions.

Common uses and compatibility

• Retain a saved message that can be reopened in a mail application.
• Examine message header fields and MIME body structure.

Things to check

• A text editor shows the serialized message; MIME parts may not be presented as readable text or separate attachments.
• The body may contain multiple content types, so the suffix does not establish one character encoding for every part.

Advanced inspection

These developer and command-line workflows inspect structure or metadata. They are not the default way most people open the file.

Technical details

Signature

Unknown

Encoding

Unknown

Container

Internet message with a header section and optional body; MIME may structure the body into parts

Compression

Unknown

Internet Message Format — RFC 5322

How to open EML in new Outlook for Windows

Microsoft documents EML support in new Outlook. Choose the application explicitly if double-clicking launches a different program.

1. Open new Outlook and locate the EML in File Explorer.
2. Drag the file onto Outlook’s reading pane, or right-click it and choose Open with > Outlook (new).
3. Read the rendered message. Treat opening or saving each attachment as a separate action.

Sources: Microsoft: open EML files in new Outlook and Outlook on the web

How do I inspect the raw message?

Open a copy in a text editor to locate the header section and the empty line before the body. Fields such as From, Date and Subject describe parts of the message, but their presence does not authenticate the sender. Preserve the original file when investigating unexpected output.

Sources: IETF RFC 5322: Internet Message Format

Why do I see MIME boundaries or encoded content?

A multipart MIME body separates parts with a declared boundary. A message can include plain text, HTML and other media; raw source is not the same view as a mail client’s rendered message. Use the mail client to interpret the structure rather than deleting unfamiliar lines.

Sources: IETF RFC 2046: MIME media types

Can I open it in a browser or convert it by renaming?

Microsoft supports dragging EML into the reading pane of Outlook on the web. That uses an online mail service; it is a different choice from reading a local copy. A browser tab by itself is not a promised EML viewer. Renaming the file to .txt can help select an editor but does not decode MIME parts or turn the message into a PDF.

Sources: Microsoft: open EML files in new Outlook and Outlook on the web · IETF RFC 2046: MIME media types

Related formats

• iCalendar

  A calendar invitation may travel with an email, but ICS event data uses a different application workflow.

• Portable Document Format

  PDF is a fixed-layout document; renaming an EML does not produce a PDF rendering of the message.