Home : File Types : PST File

.PST File Extension

File TypeOutlook Personal Information Store File

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CategoryData Files


This file is saved in a binary format, which requires a specific program to read its contents.

What is a PST file?

Data storage file that contains personal information used by Microsoft Outlook and Exchange; includes e-mail folders, contacts, addresses, and other data.

More Information

PST files have a 2 GB limit and will cause Outlook to slow down when the file is close to the limit. Microsoft provides a program called the Exchange 2000 Tool: PST2GB that will reduce the file size of a PST file. However, the utility may truncate the file meaning some data will be lost, so you should make sure to back up the PST file first.

Unlike the full version of Outlook, Outlook Express does not use PST files. However, Outlook Express can import PST data using the program's Import feature. Mac users can use the PST Import Tool for Entourage to import PST data into Entourage or the PST to MBOX Converter to convert PST files to .MBOX files.

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Programs that open PST files
Microsoft Outlook 2016
Microsoft Exchange Server
Microsoft Outlook Express
Remo Repair Outlook (PST)
BitDaddys Email Open View Pro
Encryptomatic PSTViewer Pro
OEMailRecovery.com Outlook Recovery Toolbox
Microsoft PST Import Tool for Entourage
Stellar PST to MBOX Converter for Mac
Updated 8/6/2015

.PST Extension Information

This page contains information about the file extension PST and its known file associations. Our goal is to help you understand what a *.pst file is and how to open it.

The Outlook Personal Information Store file type, file format description, and programs listed on this page have been individually researched and verified by the FileInfo team. We strive for 100% accuracy and do not publish any information we have not verified.

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