Open PST files without Outlook – on Mac and Windows
A PST file is an Outlook data file: it holds an entire mailbox or Outlook archive with all its folders, emails and attachments. Without Outlook you normally can’t open it. Mail Archive reads PST files on its own and shows every email, on Mac and Windows, for free.
Available on the Mac from version 1.3. The Windows version with these features is coming soon to the Microsoft Store.
When you need to open a PST
An old Outlook archive
“archive.pst” from AutoArchive, often years old and sitting on an external drive.
Left the company
A mailbox exported as PST, but no Outlook account left to attach it to.
Switched to Mac
You used Outlook on Windows and now work on a Mac. Apple Mail can’t read PST.
Looking for one email
You just need that one invoice or confirmation and don’t want to install Outlook for it.
How to open a PST file without Outlook
Get Mail Archive
Free for Mac (App Store) or Windows (Microsoft Store). You don’t need Outlook or an email account.
Open the PST file
Click “Open file …” at the bottom left (or press ⌘O / Ctrl+O) and choose the .pst file. You can also just drag it into the window.
Browse the folders
Mail Archive reads the folder structure (Inbox, Sent Items, your own folders) and lists every email, newest first. Pick a folder under “All folders”; the search field finds subject or sender.
Read an email
Click a message to see its text and attachments. winmail.dat attachments are unpacked automatically.
Free: viewing PST files is unlimited in the free version.
Open an Outlook archive: where is the file?
An Outlook archive is a PST file as well. On Windows it’s usually in one of these places:
Documents\Outlook Files\(e.g.archive.pstorOutlook.pst)%LOCALAPPDATA%\Microsoft\Outlook\for older Outlook versions
It’s best to copy the file to your computer or a USB stick and open the copy. While Outlook is running with the file attached, the file is locked.
Note: .ost files are not archives. They are Outlook’s offline cache for Exchange, Microsoft 365 or IMAP accounts. Mail Archive can’t read OST files from Outlook 2013 or later. In that case your emails are still on the server, so you can connect the account in Mail Archive and archive it directly.
Why won’t my PST file open?
- Proprietary format: PST is a database file with its own internal structure. Only Outlook for Windows can attach it directly.
- No Outlook installed: without Outlook, Windows doesn’t know what to open .pst with. On a Mac there’s no app for it at all; Outlook for Mac can only import PST files.
- File locked: if the file is still attached in a running Outlook, no other app can read it. Close Outlook or open a copy.
- Damaged file: after a crash or a failed copy, Outlook may no longer find the folder structure. Mail Archive then tries to read the messages from the file anyway.
- It’s actually an OST: the file ends in .ost. That’s a cache, not an archive (see above).
What Mail Archive reads from a PST
| Content | Supported |
|---|---|
| Emails with text, HTML and attachments | ✓ |
| Folder structure (Inbox, Sent, your own folders) | ✓ |
| Meeting requests and delivery reports | ✓ |
| PST from Outlook 97–2002 (ANSI) and 2003 or later (Unicode) | ✓ |
| Large files of several gigabytes | ✓ |
| Contacts, calendar items, tasks, notes | – |
| OST files from Outlook 2013 or later | – |
Mail Archive only reads the PST file. It is never modified.
Import a PST into your local archive
To keep the emails and search their full text, add the PST to your archive. After that you no longer need the PST file to read them.
From the viewer
With the PST open, click “Add to archive” at the top. The folders appear under “Imported files”.
Or via import
Under Accounts, click “Import emails (EML, MBOX)” on the account you want and choose “Outlook data file (PST)”.
Folders are kept
The PST’s folders become subfolders of a folder named after the file. Emails already in your archive are skipped.
Carry on
Then search everything, save single emails as PDF and keep them alongside your other accounts.
Adding to the archive and importing need Pro (€14.99, one-time). Viewing stays free.
No upload, no cloud
An Outlook archive often contains contracts, invoices and private correspondence going back years. Online converters want you to upload the whole PST. Mail Archive reads it on your computer. Nothing leaves your machine, and you don’t need an account with us.
To be fair: other options
- Outlook for Windows: if you have it, attach the PST via “File › Open & Export › Open Outlook Data File”. That’s the most direct route.
- Outlook for Mac: can import PST files. The emails then live in Outlook.
- Dedicated PST viewers: there are specialised tools, mostly Windows-only and often paid.
Mail Archive fits when you don’t have Outlook or you’re on a Mac, you don’t want to upload the file, and you want to keep the emails permanently and searchable.
PST questions
Can I open a PST file without Outlook?
Yes. Mail Archive reads PST files itself, no Outlook required. Viewing is free on Mac and Windows.
How do I open an Outlook archive (archive.pst)?
Like any other PST: use “Open file …” in Mail Archive or drag the file into the window. If it’s still attached in Outlook, close Outlook first or open a copy.
Can I open a PST file on a Mac?
Yes. Mail Archive runs on Mac and Windows, and PST support is the same on both.
Does it open OST files?
No. Mail Archive can’t read OST files from Outlook 2013 or later. An OST is only a cache; your emails are still on the server, so connect the account in Mail Archive instead.
How much does it cost?
Viewing is free. Adding to the archive is part of Pro, €14.99 one-time, no subscription.
Are contacts and calendars imported?
No. Mail Archive is an email archive and only reads emails, meeting requests and delivery reports from a PST, each with attachments.
Mail Archive does more
Your Outlook archive, without Outlook
Get Mail Archive for free and view PST files right away. Add them to your archive with Pro, €14.99 one-time.