Paperclip

Opens the email files your Mac can’t.

On the App Store · Mac, iPhone and iPad

Windows Outlook keeps sending files your Mac can’t read: winmail.dat attachments and .msg message files. Paperclip opens them instantly, with the message’s real formatting, every attachment, and the calendar invite hiding inside. It also opens and searches entire .pst archives without importing them or sending anything off your Mac. There’s a viewer for iPhone and iPad too. Paperclip will never be a subscription.

Viewing is free. Forever.

Open .msg, winmail.dat, and .eml files, or search an entire .pst archive. Read each message with its real formatting. See every attachment and drag it to Finder. No trial timer, no watermark, no nag.

It never silently drops anything.

Other apps quietly skip what they can’t decode; you find out weeks later that the contract was in the part that didn’t open. Paperclip surfaces every piece of the file, and when something truly can’t be recovered, it tells you what, where, and why: “this attachment is truncated at byte 52,114; here’s what was recovered.” Real diagnostics, not a shrug.

The meeting invite actually works.

winmail.dat files usually carry a meeting request. Paperclip decodes it, including recurring meetings, moved occurrences, and time zones, and hands Calendar a correct .ics. If a repeating pattern can’t be expressed faithfully, Paperclip says so instead of putting the meeting on the wrong day.

Fully Mac-native.

Quick Look: press space on a .msg in Finder. Drag attachments out. Print. Save everything at once. Nested messages open in place.

Your mail never leaves your Mac.

Zero telemetry, zero analytics, no account, no server. Remote images are blocked by default, which also blocks tracking pixels. The App Store privacy label says “Data Not Collected” because there is nothing to collect it with. Details in the privacy policy.

Viewing is free. Pro is one purchase.

Opening, reading, searching, printing and Quick Look are free, always. Paperclip Pro is a one-time in-app purchase. On the Mac it adds PDF and .eml export, batch conversion and saving several attachments at once; on iPhone and iPad, sharing a message as PDF or .eml. One purchase covers all your devices and works with Family Sharing. Downloaded Paperclip during the launch period? Then you already have Pro, free, for good. Not a subscription. There are no servers to feed.

What it doesn’t do

It won’t send mail, sync anything, or replace Mail. And Quick Look previews cover .msg files only; macOS reserves winmail.dat and .eml for its own handlers. Paperclip opens the files your Mac can’t. That’s the job, and it stays the job.

Get it

Paperclip on the App Store. One download covers Mac (macOS 15 or later, Apple silicon), iPhone and iPad. If a file doesn’t open, tell me; that’s a bug, and I treat it like one.

Changelog

2026-11: 1.1: Paperclip Pro, a one-time purchase (free for good if you downloaded during launch). iPhone and iPad can print a message or share it as a PDF. On the Mac, Share as PDF and Export as PDF… sit in the toolbar’s Share button. Printed and PDF meeting invites show when, where, who and how often. Fixed: printing a plain-text message on the Mac cut it off after about a page.
2026-10: 1.0.2: editing an attachment in another app no longer risks losing your copy. Some damaged .msg files that wouldn’t open now do, with a note on what was recovered. Quick Look shows meeting details.
2026-09: 1.0 on the App Store: Mac, iPhone and iPad. 1.0.1 for iPhone and iPad adds a Done button to attachment previews.
2026-08: Mac beta on TestFlight (viewer, export, batch convert, Quick Look, privacy-safe diagnostics). iOS companion in early testing. Outlook archive browsing in progress.

Support

It’s just me here, and I answer email, usually within a day: support@offmetalabs.com. Common questions are answered on the support page.