PST (Personal Folders File)

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Definition: PST or Personal Folders File is the format used by Microsoft Outlook to store data locally.

The PST file—or PST files; you can use multiple PST files with one copy of Outlook simultaneously—holds emails, contacts, notes, the ​to do calendars and other Outlook data.

The use of a single database for all data makes PST files grow rapidly and to significant sizes. Even when the PST file size limit is not yet reached, it is recommended you ​use multiple smaller PST files to ward off the danger of file corruption and slow access times.

Also Known As: Personal Storage Table