The .msg file on a Mac
How to open a .msg file on a Mac without Outlook
A .msg file is an Outlook message saved to disk, and on a Mac without Outlook a double-click does nothing useful. Here is what you are looking at and the ways in, free ones first.
What a .msg file actually is
A .msg is a single Outlook message saved out of a mailbox. Inside, it is a small structured container — the same family of file older Word and Excel documents used — holding the message text, the header fields, the recipients and each attachment as a separate stream. That is why only software that understands that container can open it. Quick Look will not preview it and Apple Mail will not import it.
Renaming it to .eml does not work
This is the most common suggestion online and it fails every time. An .eml is a plain-text internet message; a .msg is a binary container. Changing the extension changes nothing inside, and Mail will not open it.
The free routes
Outlook for Mac — if you have it
If you have Outlook, it opens .msg files directly (double-click, or File → Open). From there, Print → Save as PDF gives you the message body as a PDF. Attachments are saved separately.
Verdict: the simplest route when Outlook is already installed; one message at a time; attachments not in the PDF.
A mail client with a .msg import add-on
Some mail clients can import .msg files with an add-on. It is free, it works for reading, and it puts the message into a mail folder rather than giving you a document.
Verdict: good for reading a few; a detour if what you need is files to hand over.
Ask the sender for the message as .eml or PDF
Outlook users can drag a message to the desktop or use Save As with a different type. If the sender is reachable, this is the zero-effort route.
Verdict: fine for one; not for an archive somebody left behind.
A free online converter
They read .msg — after you upload it.
Verdict: for anything confidential, the wrong trade; it is usually confidential correspondence that arrives this way.
Where Foldavo fits
Foldavo opens the .msg container itself, on a Mac (and on Windows), so it needs no copy of Outlook. Each message becomes a PDF named from the sender, subject and date, with the header block at the top and the attachments embedded inside the same PDF; an Outlook message that was itself attached (a .msg inside a .msg) becomes a further section of the same PDF, with its own attachments; an email attached to an .eml is embedded as a file. It decodes the older Chinese, Japanese and Korean encodings Outlook used (Big5, GBK, Shift-JIS and EUC-KR). The free trial converts one message completely; a licence (£59, one-time) does a whole folder of them. Nothing is uploaded. Checkout by Lemon Squeezy.
Being straight with you: Foldavo reads .msg and .eml files saved to disk. It does not read a .pst mailbox archive — export the messages first. Attachments are embedded inside the same PDF and listed in the PDF's attachment panel — they are never opened or executed. Inline JPEG and PNG images are drawn on the page as well; every other attachment stays the file it was, one click away inside the PDF. Text in Latin, Greek, Cyrillic, Hebrew, Arabic, Chinese, Japanese and Korean scripts is rendered; Thai, Indic scripts and emoji are shown as a question mark. Rich formatting is simplified: the text, the structure and the record are preserved; the message's exact fonts and layout are not reproduced.