How to Open a PST File in Outlook

Opening a PST file in Outlook depends on your version and whether the file is already connected to your account

A PST file is Outlook's native format for storing email, calendar events, contacts, and tasks. If you have a PST file on your computer — perhaps from a backup, a transfer from another computer, or an export from someone else — you can open it in Outlook by importing it or by adding it as a data file. The exact steps differ slightly between Outlook on Windows, Outlook on Mac, and Outlook on the web, and the method you use depends on whether you want to merge the PST into your existing mailbox or keep it separate.

The fastest route is usually to decide first whether you want the contents mixed with your current mail or kept separate. If you want them merged, use the import function. If you want them to stay in their own folder, add the PST as a data file instead. Both methods take only a few minutes to set up.

Key Takeaways

Windows Outlook users can import a PST file through File > Open & Export > Import, which merges the contents into your current mailbox.
To keep a PST file separate from your main mailbox, add it as a data file instead of importing it, and it will appear as a folder in your left sidebar.
Outlook on Mac does not support PST files natively; you must convert the file to OLDATA format first using a third-party tool or export the contents differently.
Outlook on the web cannot open PST files directly; you must import the file through the desktop version first, then access it through your web browser.
If Outlook does not recognize the PST file, the file may be corrupted; use the Inbox Repair Tool (scanpst.exe) on Windows to attempt recovery before importing.

Importing a PST file into Windows Outlook

The most common way to open a PST file in Outlook on Windows is to import it. This merges the email, contacts, calendar, and other items from the PST into your current mailbox or into new folders within your account. Open Outlook and go to File in the top left. Click Open & Export, then select Import/Export. A wizard window will open.

In the Import and Export Wizard, select Import from another file and click Next. Choose Outlook Data File (.pst) from the list and click Next again. Click the Browse button, navigate to the PST file on your computer, select it, and click Open. The wizard will then ask where you want the imported items to go — you can merge them into an existing folder or create new folders. Follow the prompts to completion, and Outlook will import the contents.

Adding a PST file as a separate data file instead of importing

If you want to keep the PST file separate from your main mailbox — for example, to preserve an archive or to access an old account without mixing it with current mail — you can add it as a data file. This displays the PST as a folder tree in your left sidebar without merging anything. Go to File, then Open & Export, and select Open Outlook Data File. Browse to the PST file, select it, and click Open.

Outlook will add the PST file to your sidebar under its original name. You can now view, search, and copy items from it without affecting your main mailbox. To remove it later, right-click the data file name in the sidebar and select Close "[File Name]". The PST file itself remains on your computer; closing it in Outlook straightforward disconnects the view. You can open it again at any time by repeating the same steps.

Opening a PST file on Outlook for Mac

Outlook for Mac does not support PST files. If you have a PST file and use Outlook on Mac, you must convert it to OLDATA format first. You can do this by opening the PST file in Windows Outlook, exporting the contents as an OLDATA file, and then transferring that file to your Mac. Alternatively, some third-party conversion tools can convert PST to OLDATA or to standard formats like CSV or ICS, though these tools vary in reliability and cost.

If you do not have access to Windows Outlook, another option is to export the PST contents to individual formats — for example, export email as MSG files or EML files, export contacts as a VCF file, and export calendar as an ICS file — and then import each format separately into Outlook for Mac. This is more time-consuming but avoids the need for conversion software. Check the Mac App Store or search online for "PST to OLDATA converter" if you want to try a third-party tool.

Accessing a PST file through Outlook on the web

Outlook on the web (the browser version at outlook.com or outlook.office.com) cannot open PST files directly. However, once you import a PST file into Outlook on Windows or Mac, the contents will sync to your online account and become visible in the web version. Import the PST through the desktop app first, wait for synchronization to complete (usually within a few minutes), and then log into Outlook on the web to view the imported items.

If you need to access the PST file only through the web and do not have the desktop app, you will need to export the PST contents to a different format — such as CSV for contacts or ICS for calendar — and then import those files into Outlook on the web individually. The web version has an import feature under Settings > Mail > Accounts > Import email, though it accepts fewer file types than the desktop version. This approach works best for smaller PST files with specific content you want to move.

Repairing a corrupted PST file before opening

If Outlook shows an error when you try to open or import a PST file, the file may be corrupted. Windows Outlook includes a built-in repair tool called the Inbox Repair Tool (scanpst.exe). To find it, search your computer for "scanpst.exe" — the location varies by Outlook version, but it is typically in C:\Program Files\Microsoft Office\root\Office16\ or a similar path. Run the tool and browse to the PST file you want to repair.

Click Start to scan the file. The tool will report any errors it finds and offer to repair them. Allow it to complete the repair, which creates a backup of the original file (usually named with "_backup" in the filename). Once repair is complete, try importing or opening the PST file again in Outlook. If the tool cannot repair the file, the damage may be too severe, and you may need to consult a data recovery service or try a third-party PST recovery tool.

Moving or backing up a PST file safely

PST files can be large and should be handled carefully. If you need to move a PST file to a different location or computer, close it in Outlook first — do not move or copy a PST file while Outlook has it open, as this can corrupt it. Once closed, you can safely copy the file to a new location using Windows File Explorer or Mac Finder. If you are transferring the file to another computer, copy it to an external drive or cloud storage, then move it to the destination computer before opening it in Outlook.

For backup purposes, periodically copy your PST files to an external drive or cloud storage service. Many people keep their PST files in the default Outlook data folder (usually C:\Users\[Your Name]\AppData\Local\Microsoft\Outlook\ on Windows), but you can also store them elsewhere and add them to Outlook as needed. Keeping a backup copy protects you against accidental deletion or drive failure. Label your backups with dates so you know which version is most recent.

Frequently Asked Questions

Why does Outlook say the PST file is not an Outlook data file?

This usually means the file is corrupted or the file extension is wrong. Verify that the file actually ends in .pst and not .pst.bak or another extension. If the extension is correct, try running the Inbox Repair Tool (scanpst.exe) to repair corruption. If the tool cannot fix it, the file may have been damaged during transfer or storage.

Can I open a PST file without Outlook installed?

Not directly. You need Outlook or a third-party PST reader to view the contents. Some free tools can read PST files without Outlook, but they vary in completeness and reliability. If you only need to extract specific items, exporting the PST to CSV or ICS format in Outlook first is usually more reliable.

What is the difference between importing and adding a PST file as a data file?

Importing merges the PST contents into your current mailbox or into new folders within it, making the items part of your main account. Adding it as a data file keeps the PST separate and displays it as a distinct folder tree in your sidebar, without merging anything. Use import if you want to consolidate mail; use data file if you want to preserve an archive or old account separately.

How long does it take to import a large PST file?

Import time depends on the file size and your computer's speed. Small files (under 100 MB) usually import in a few minutes. Large files (1 GB or more) can take 30 minutes to several hours. Do not close Outlook or disconnect from the internet during import, as this can interrupt the process and corrupt the file.

Can I edit items in a PST file after opening it?

Yes, once a PST file is imported or added as a data file, you can edit, delete, move, and copy items within it just as you would in your main mailbox. Changes are saved to the PST file itself. If you want to preserve the original PST unchanged, make a backup copy before opening it in Outlook.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.