PST File Extension
Outlook Personal Information Store Format
- File Type pst
- Developer Microsoft
- Popularity
- Application Microsoft Outlook
- Category Email Program Files, Data Files
- Format Binary
What is a PST file?
The PST file extension is linked to Outlook Personal Information Store Format and belongs to the categories of Email Program Files and Data Files, which include 6246 files.
The Outlook Personal Information Store Format (PST) was developed by Microsoft, which created file format and 242 programs to work with them.
PST file support extends to various operating systems, including Windows, Mac OS and Linux. To open a PST file, you can choose from 25 programs such as Microsoft Outlook, Microsoft Entourage and Microsoft Exchange Server.
File Signature
HEX code: 21 42 44 4E. ASCII code: !BDN.
Programs that support PST files
Windows
Microsoft Outlook
Microsoft Exchange Server
EML Viewer Pro
Microsoft 365
Aid4Mail- SysTools OST Recovery
- MBOX to PST Converter Tool
- DBX to PST Converter
- Outlook Mac Exporter
- SysTools Exchange EDB To PST Converter
- Advanced Outlook Repair
- MBOX to PST Converter
- MSG 2 PST
- Advanced Office Repair
- SoftSpire vCard Converter
- MBOX Viewer
Microsoft Office- OLM File Exporter
- Aid4Mail MBOX Converter
Mac OS
How to open a PST file?
If you cannot open a PST file, it is most often due to missing software. Select a program from the list according to your operating system. Then go to the official website of the program developer, download it, and install it on your device.
When it comes to opening and working with PST files, Microsoft Outlook, Microsoft Entourage and Microsoft Exchange Server are the top choices for users. If you want the most recent release of Microsoft Outlook, head over to the Microsoft site and download the version designed to run on all platforms.
Once the process is complete, Microsoft Outlook should take over as the default application for PST files.
Set Microsoft Outlook as the default PST application
Changing Default Programs in Windows
- Right click on your PST file, then select "Open with" and click "Choose another application";
- From the options listed in the pop-up window, specifically choose Microsoft Outlook as the application to handle your PST file;
- Be sure to check the "Always use this app" checkbox and click "OK" to save your preference.
Change the default app that opens a file on Mac
- Right-click or use Control + Left-click on the desired PST file to open a menu where you can choose from multiple actions;
- Select "Open in application" and click "Other";
- At the bottom of the window, you will find the "Enable" menu. Default, will be set to "Recommended Programs";
- Choose "All Programs" in this menu and search for Microsoft Outlook. Check the box next to "Always open in app" to make it the default program.
Troubleshooting guide for PST file complications
Rest assured, any issues with PST files can typically be addressed with simple software adjustments. See the tips below for help.
What Causes Microsoft Outlook to Crash Frequently?
The likely cause of Microsoft Outlook crashing is lack of software updates. Install the latest updates available for Microsoft products.
Restarting your computer is a crucial troubleshooting measure that can alleviate numerous common problems. Therefore, it is advisable to restart your computer before modifying any settings related to the software.
How can I restore a damaged PST file?
Open the corrupted PST file in Aid4Mail, Advanced Outlook Repair or Advanced Office Repair and select the "Repair" menu item. Please be patient while the recovery process completes, which will automatically restore the damaged email program files.
How do I know if my PST file is corrupted?
Common indications of damaged PST email program files are:
- Attempts to open the file result in errors or failed results;
- Editing the archive in Microsoft Outlook results in slow or unresponsive behavior;
- The file causes Microsoft Outlook or other programs to hang or crash during operation;
- Unexplained increase in PST file size;
- Error messages appear while working with the file;
How to edit a PST file?
To edit PST files, it is essential to install software that supports not only viewing but also editing the email program files. Online PST editors provide limited functionality compared to full-featured software for Outlook Personal Information Store Format.
Best PST editors in 2026
Based on the criteria above, here is a selection of PST editors you can use.
| PST Editor Software | Developer | Platforms | Overall Rating |
|---|---|---|---|
| Microsoft Outlook | Microsoft | Windows, Mac OS | 4.5 out of 5 (46 reviews) |
| Microsoft Entourage | Microsoft | Mac OS | 4.1 out of 5 (47 reviews) |
| Microsoft Exchange Server | Microsoft | Windows | 4.1 out of 5 (42 reviews) |
Convert to and from PST
If working with a PST file is challenging, one solution is to convert it to formats like MBOX, ICS or other supported formats.
Keep in mind that converting a PST file may introduce some limitations, but the original format can often be restored.