1. PST File Extension
2. What is a(n) PST file?
3. How to open PST file?

3.1 Download and install application that supports PST files
1. 3.1.1 Programs that support PST files
3.2 Verify whether PST files are associated with appropriate software
3.3 Check PST file for other errors

4. Similar file extensions

PST File Extension

File type Outlook Personal Information Store Format
File developer Microsoft
File category Data Files
File popularity rating

What is a(n) PST file?

The PST (Outlook Personal Information Store Format) is a file format used to store information in Microsoft Outlook. It is the main data container for Outlook which stores emails, contacts, calendars, tasks, and other Outlook items. PST files are usually stored locally on the users computer and can be accessed via Microsoft Outlook.

PST files can also be saved as an archive file, enabling users to create backup versions of their email and other Outlook content. The size of a PST file can be limited by the user or administrator of an Exchange mailbox, which will cause the older content to be archived into separate PST files.

How to open PST file?

If given user account does not have necessary permissions to open files with PST extension, it is highly probable that no program that supports given files is installed on the users’ system. Below is a list of actions user should pursue in order to resolve most common problems.

Step 1. Download and install application that supports PST files

After the application has been installed, the system should automatically open PST files with given application. Below is the list of relevant programs along with operating systems they are available for:

Programs that support PST files

Windows

MAC OS

Microsoft Entourage

Step 2. Verify whether PST files are associated with appropriate software

It is possible that an application that supports PST files is not associated with such files. In such case, the program should by manually associated with PST files (right-click on the file icon → Properties → General Tab → In submenu "Open with" and click on "Change" button. System will display a list of suggested programs that support PST files. Choose the application by checking the box "Always use the selected application to open this kind of files". System will store this information in its registry and use it to open PST files with the selected program.

Changing PST file association in registry

File association for PST files can be edited manually by editing appropriate entry in Windows System Registry. However, it is discouraged as it may introduce errors to registry if not done properly and may even damage the system.

Step 3. Check PST file for other errors

PST file was not copied properly from storage medium.
Antivirus application prevents opening PST files. In that case it is recommended to exercise extreme caution and recover or delete infected PST file. It is also advised to scan the entire system for malicious software and viruses with antivirus software.
For PST files downloaded from the internet it is advised to check if the file has been downloaded completely and is not corrupted. If not, the file should be re-downloaded.

Similar file extensions

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