Your files stay on your device. Nothing is uploaded.

4n6

Online Pegasus Mail Viewer

Open Pegasus Mail PMM, CNM and PMI files right in this browser tab.
Read the message, check the headers, save the attachments.

Open Pegasus FileFree, no signup, no install Need to Convert?See 4n6 Pegasus Converter

100% Browser BasedFree for Home and Business Use

Version 6.8  |  Works in Chrome, Edge, Firefox and Safari

  • Opens PMM, CNM, PMI, PML and PMF files
  • Reads a whole PMAIL folder in one go
  • Nothing is uploaded, every byte stays local
  • HTML, plain text, header and attachment tabs
  • Old DOS and NetWare mail decodes correctly
  • Full message headers on their own tab
  • Search and sort thousands of messages
  • Free with no message limit
★★★★★4.8 Average Rating • 186 Verified Reviews
🌟
Completely FreeNo Message Limit
🔒
No Upload StepFiles Never Leave Your PC
👁
Read OnlyYour Mailbox Is Untouched
⚡
Nothing to InstallRuns In Any Browser
The Viewer

Open Your Pegasus Mail File Right Here

Pick a single .PMM folder or point the viewer at your whole PMAIL directory. Reading starts as soon as the file is chosen.

Your mail stays with you. Pegasus files are read by this page inside your browser. No copy is sent to 4n6 or anywhere else.
Messages
Open a Pegasus file to begin.
Select a message from the list to read it here.

Drop a Pegasus Mail file here

Choose one .PMM folder, a handful of .CNM messages or your entire PMAIL directory. The file opens in this tab and never leaves your computer.

.PMM.CNM.PMI.PML.PMF.PMN.PNM.PMC.MBXHIERARCH.PM

Works offline once the page has loaded. Nothing is stored, so closing the tab clears everything.

Reading Pegasus files
📁
Folder Names KeptRead From HIERARCH.PM
🔍
Search and SortAcross The Whole Folder
📎
Attachments OpenPreview Or Download
🔍
Full Header ViewThe Whole Routing Trail
Supported File Types

Every File Pegasus Mail Leaves Behind

A PMAIL directory holds more than mail folders. Here is what the viewer does with each file it finds.

ExtensionWhat Pegasus Stores In ItWhat The Viewer Does
.PMMA mail folder holding many messages end to endSplits it into messages and lists every one
.CNMA single new mail message waiting in the queuePools them into one New mail folder you can browse
.PMIThe index that Pegasus keeps beside a folderIdentifies it and points you to the matching .PMM
.PMLA distribution list of names and addressesShows the full address table on the right
.PMFAn attachment file saved out of a messageReads any mail content and offers the file
.PMN / .PNMNotepad entries and message annotationsOpens the note text as a message
.MBX / .PMGOlder DOS and NetWare mailbox filesHandled with the same folder parser
HIERARCH.PMThe tree that maps file names to folder namesRenames the folder list to what you saw in Pegasus

Configuration, cache and lock files in the same directory are skipped, so picking the whole PMAIL folder does not fill the list with junk.

Key Features

What This Pegasus Mail Viewer Does for You

Pegasus wrote mail in its own way for 35 years. The viewer covers the whole range.

Read PMM Files With No Pegasus Install

The parser walks the folder itself and finds each message boundary. You do not need Pegasus Mail, an old PC or a licence to see what is inside an archived mailbox.

Your Mail Never Leaves The Device

There is no upload and no server round trip. The page reads the file with the browser File API, so a mailbox full of client correspondence stays on your own disk.

Whole PMAIL Directory In One Pick

Choose the folder instead of a file and the viewer sorts what it finds into mail folders, new mail, notes, lists and index files. HIERARCH.PM restores the names you knew.

Old Code Pages Decoded Properly

DOS and NetWare mail arrives in CP437, CP850, CP852, CP865 and friends, which browsers do not support. Those tables are built in, alongside Windows, ISO, KOI8, Shift_JIS, GBK, Big5, EUC-KR and Unicode.

Attachments Come Out Whole

Base64 and quoted printable parts decode, and so do the uuencoded and BinHex attachments common in 1990s mail. Images preview in place and any file downloads with one click.

Big Folders Stay Quick

The file is scanned in 4 MB chunks and only the header of each message is held for the list. Scrolling stays smooth at thousands of messages because rows are drawn as you reach them.

Message HTML Is Rendered Safely

Scripts, forms and event handlers are stripped, then the body is drawn in a sandboxed frame. Remote images wait until you press Load images, so a sender cannot log that you opened the mail.

Four Views Of Every Message

HTML for the formatted mail, Text for the plain body, Headers for the full routing trail and Files for the attachments. Investigators get the raw header list without a separate tool.

A Clean Handover To The Converter

Reading is free here and always will be. When the mail has to move into Outlook, a PDF set or another mailbox, the 4n6 Pegasus Converter handles the export in batch.

How It Works

Open Pegasus Mail Files in 3 Steps

No download and no account. The first message is on screen in about 10 seconds.

1
Pick Your FileOr drag it onto the page

Use Choose Pegasus Files for one mailbox or Choose a Folder for the whole PMAIL directory. Drag and drop works anywhere on the viewer card.

2
Browse The FolderSearch, sort, click

Folders appear on the left with a message count each. Sort by date, filter by sender or subject, then click a row to read the full message.

3
Read Every PartBody, headers, attachments

Switch between HTML, Text, Headers and Files. Open an attachment straight from the Files tab. To export the mail itself, move over to the 4n6 Pegasus Converter.

What Happens After You Pick A Pegasus File

How the 4n6 online Pegasus Mail Viewer opens a file 1. Sort The Files Folders, new mail, notes and lists 2. Split And Index Every message header is read 3. Read Any Message Body and attachments load on click

Only headers are read up front. That is why a 400 MB folder lists in seconds instead of minutes.

Who Uses It

A Browser Pegasus Viewer Solves Real Problems

🗃

Anyone Holding An Old Mailbox

A backup drive from an old office PC has a PMAIL folder on it. You need to know what is in there before you decide whether to keep any of it.

🔎

Forensic and Legal Review

Examiners need message headers and dates without altering the evidence file. The viewer opens read only and shows the full header trail on its own tab.

💼

IT Teams Planning A Migration

Before quoting a Pegasus to Outlook project, someone has to count the folders and check the mail is intact. Open each PMM file on any machine and find out.

🏫

Universities and Labs

Pegasus ran on campus NetWare networks for years. Old research correspondence still sits in PMM files that no current mail client will touch.

📧

Someone Sent You A .CNM

A single Pegasus message arrives and nothing on your PC opens it. Drop it here and read it in a few seconds without installing anything.

🔒

Anyone With Confidential Mail

Upload based converters are out of the question for privileged or regulated mail. This page reads the file locally, so nothing crosses the network.

Which One Do You Need?

Online Viewer or Pegasus Converter?

Reading is free in the browser. Batch export is the desktop job.

This Online Viewer

Free forever

Made for reading. Open a Pegasus folder, find the message you want and check its body, headers and attachments. Exporting is not part of it.

Pick the viewer when you want to:

  • Read a PMM or CNM file someone sent you
  • Check an old archive before deciding its fate
  • Look up one message, date or address
  • Check headers before a case or a migration
  • Work on a machine where you cannot install software

4n6 Pegasus Converter

Windows desktop app

Made for moving mail. It exports whole Pegasus mailboxes to PST, PDF, MBOX, MSG, EML and cloud accounts with the folder tree kept intact.

Move up to the converter when you need to:

  • Migrate a full mailbox to Outlook or Microsoft 365
  • Convert thousands of messages in one run
  • Apply date, sender or attachment filters
  • Produce PDF sets for a case or an audit

Explore 4n6 Pegasus Converter

Honest Comparison

4 Ways to Open a Pegasus File, Compared

Each route works for someone. Here is what you actually get from each one.

Pegasus Mail Viewing Options

This online viewer vs upload sites, Pegasus Mail itself and a desktop converter

What Matters This Viewer Upload Sites Install Pegasus Mail Desktop Converter
Price to read a fileFreeFree with limitsFreeFree trial
File stays on your device✓ Yes✗ Uploads✓ Yes✓ Yes
Anything to installNothingNothingFull mail clientWindows app
Works on Mac and Linux✓ Yes✓ Yes✗ Windows only✗ Windows only
Old DOS code pages✓ YesHit or miss✓ Yes✓ Yes
Batch export to PST or PDF✗ NoLimited✗ No✓ Yes

The fair print. Installing Pegasus Mail still works if you have a Windows PC and the patience to set up a mailbox. Upload sites are fine for a file with nothing private in it. This page suits a quick read on any device, and the desktop converter is the tool once the mail has to move somewhere else.

Privacy

Where Your File Actually Goes

Nowhere. When you pick a file, the browser hands this page a read only handle to it. JavaScript on the page reads the bytes, splits the folder into messages and draws them on screen. There is no request that carries your mail anywhere.

You can prove it. Open the network tab in your browser tools, load a PMM file and watch: no upload appears. Turn off your internet after the page has loaded and the viewer keeps working.

Nothing is stored either. Close the tab and every trace of the file is gone from the page.

Built for sensitive mailboxes

🔒 No upload, no account, no cookies for the viewer

👁 Read only. The source file is never written to

🧲 Message HTML runs in a sandboxed frame with scripts stripped

📷 Remote images blocked until you ask for them

Technical Details

Online Pegasus Mail Viewer Specifications

OpensPMM, CNM, CNB, CNR, CNX, PMI, PMG, PML, PMF, PMN, PNM, PMC, MBX and HIERARCH.PM
Runs OnChrome, Edge, Firefox, Safari, Opera and Brave on Windows, macOS, Linux, Android or iOS
Pegasus Mail RequiredNo. The page parses the format on its own
Character SetsCP437, CP775, CP850, CP852, CP857, CP860, CP861, CP863, CP865, CP866, Windows 1250 to 1258, ISO 8859 family, KOI8-R, KOI8-U, Shift_JIS, ISO-2022-JP, GBK, Big5, EUC-KR, Macintosh, UTF-8 and UTF-16
Attachment EncodingsBase64, quoted printable, 7bit, 8bit, binary, uuencode and BinHex
Message ExportNot included. Viewing only. Export to PST, PDF, MBOX, MSG and EML lives in the 4n6 Pegasus Converter
Data HandlingLocal only. Files are read in the browser and never uploaded or stored
PriceFree for personal and business use

Product Guide Talk to Support

Industry Recognition

A Free Tool Held to Paid Standards

4n6 has built email forensics tools since 2013. The same parsing work goes into the free ones.

CNET Award
★★★★★

CNET, 5 Star Rating

Five stars across the 4n6 range for tools that do the job with nothing bundled on the side.

Software Informer Award
★★★★☆

Software Informer, 4.5 Stars

Reviewers singled out how little there is to learn. Pick a file, read the mail, done.

★★★★★

Used by Investigators

4n6 trains law enforcement teams on email evidence handling. This viewer follows the same read only rule.

Verified Reviews

Online Pegasus Mail Viewer Reviews

★★★★★

"A client handed us a drive with a PMAIL folder on it from 1998. I pointed this page at the folder and had the whole mailbox listed with real folder names in under a minute. Nothing left the machine, which is the part legal cared about."

RG
Rob Gillespie
Digital Forensics Analyst
✓ Verified
★★★★★

"Our old NetWare mail was full of German umlauts that came out as garbage in every other tool I tried. This one read them correctly straight away. That alone saved me a week of guesswork."

SK
Sabine Krause
Systems Administrator
✓ Verified
★★★★★

"My father ran Pegasus Mail until he retired. After he died I had a folder of PMM files and no way to read them. I opened every one of them here on a Mac and finally knew what was in them. Thank you for making this free."

HM
Helen Marsh
Home User
✓ Verified
Common Questions

Frequently Asked Questions About
Viewing Pegasus Mail Files

Straight answers before you open anything.

Drop the .PMM file onto the viewer above. Pegasus stores messages one after another inside the folder file, separated by a control character. The viewer finds those breaks, reads each message header and lists everything. Pegasus Mail does not need to be installed and the file is never uploaded.

PMM mail folders, CNM new mail messages, PMI folder indexes, PML distribution lists, PMF attachment files, PMN and PNM annotations, PMC data files plus the legacy MBX and PMG mailboxes. HIERARCH.PM is read as well, so your folder list shows the names you used in Pegasus instead of file names like FOLD0003.PMM.

No. Every byte is read by JavaScript inside your own browser tab using the standard File API. Nothing is sent to 4n6 or to any other server. If you disconnect from the internet after the page loads, the viewer still opens files normally. That is the simplest way to confirm it for yourself.

Pegasus keeps unfiled mail as separate CNM files, one per message. When you open a folder holding many of them, the viewer pools them into a single New mail folder so you can scroll the lot instead of opening 300 files by hand. Filed mail lives in PMM folders and appears under Mail folders.

No. This page is a viewer, so it reads Pegasus files and shows them without writing anything out. Message export is the job of the 4n6 Pegasus Converter, a Windows app that saves whole mailboxes to PST, PDF, MBOX, MSG, EML and cloud accounts in one run. Attachments are the exception. Any file inside a message can be opened from the Files tab.

Yes. Pegasus began on NetWare and DOS in 1990, so old folders often hold CP437, CP850, CP852 or CP865 text. Browsers dropped support for most of those code pages, so the tables are built into this viewer. Windows 1250 to 1258, the ISO 8859 family, KOI8, Shift_JIS, GBK, Big5, EUC-KR and Unicode are handled too, and encoded header words are decoded before display.

Yes. MIME parts encoded as base64 or quoted printable are decoded, and so are the older uuencoded and BinHex attachments that turn up in 1990s mail. The Files tab previews images and lists everything else with its type and size, and each one can be opened from there.

Large ones. The file is scanned in 4 MB chunks and only the first part of each message is kept for the list, so memory stays low. A folder with thousands of messages lists in seconds. The full body and its attachments are read only when you click that message.

Images hosted on a remote server are blocked until you allow them, because fetching one tells the sender the message was opened and leaks your address to their tracker. Press Load images in the yellow bar to fetch them for that message. Images stored inside the message itself display right away.

Yes. The viewer is a web page, so any current browser on Windows, macOS, Linux, Android or iOS runs it. Pegasus Mail itself is Windows only, which is why reading its files on a Mac used to mean borrowing a PC. On a phone the message list and the reader swap places to fit the screen.

Same understanding of the format, different jobs. This page reads Pegasus files and nothing more, free and with no install. The 4n6 Pegasus Converter is a Windows app that batch exports whole mailboxes to PST, PDF, MBOX, MSG, EML and cloud accounts with filters and the folder tree kept intact. There is also a guide on moving Pegasus Mail to Office 365.

Your Pegasus Mail Is One Click From Readable

No install, no signup, no upload. Pick a PMM or CNM file and read it in this tab.

Open a Pegasus File See the Converter

Any Browser  |  Nothing Uploaded  |  Free for Home and Business Use