How to open a .pst file
Outlook data file · Email
A .pst file is an entire Outlook mailbox in one file. Outlook opens it directly. Without Outlook you need a conversion tool, because unlike .mbox it is a proprietary binary database.
What a .pst file actually is
PST stands for Personal Storage Table. It holds messages, contacts, calendar entries and tasks in a single indexed database file, which is how Outlook archives mail off a server.
It is proprietary and binary. Microsoft documents the structure, but no mainstream free client imports it directly, which is the practical problem people hit.
Why it will not open
Nothing outside Outlook reads PST natively. Thunderbird cannot import one directly, and neither can Apple Mail, so a PST handed over on a USB stick is genuinely awkward to open.
Step by step
Windows
- 01With Outlook: File, Open & Export, then Open Outlook Data File, and pick the .pst. It appears as a folder tree in the sidebar.
- 02If the file is damaged, Outlook ships a repair tool called SCANPST.EXE, in the Office installation folder. Run it against the file first.
- 03Without Outlook, the practical route is a PST conversion tool that exports to EML or MBOX, which Thunderbird then imports.
- 04If the mailbox is still on a server, do not bother with the PST at all: connect the account and download the mail again.
macOS
- 01Outlook for Mac imports PST via File, Import.
- 02There is no native macOS support otherwise, so conversion on a Windows machine is usually the shortest path.
What usually goes wrong
A password-protected PST is not encrypted
The old PST password is a weak access check rather than real encryption, and tools that strip it are widespread. That cuts both ways: do not treat a PST as a secure container for sensitive mail.
Programs that open .pst
Our pick, in order. Every one links to the publisher's official download URL and the SHA-256 hash of the installer, so you can check the file before you run it.
Common questions
- How do I open a PST file without Outlook?
- You need to convert it first, since no mainstream free client imports PST directly. Export to EML or MBOX and then import that into Thunderbird, which reads both.
- What is the difference between PST and OST?
- A PST is a portable data file you can move and open elsewhere. An OST is a cached local copy of a server mailbox, tied to that account and profile, and is not designed to be opened independently.