.pst is a Person Folders file, and stands for Personal Information Store. .pst is a data storage format used by various Microsoft software such as Outlook in order to save your information. Some of the things kept in .pst files are:
- Saved e-mail messages
- Calendar appointments
- To-do list data
If you use a workstation that lives on a network with many other computers, your .pst file is kept on your hard drive, but synchronized back and forth in your network profile. This enables you to retrieve your e-mail and calendar data no matter which computer you log into.
You should not try to modify a .pst file, nor move it to a new location. Doing so could cause you to lose important e-mail and calendar data.
