About the Outlook PST-File

A PST-file is the file Outlook uses to store its items in for all accounts other than an Exchange account. It also holds some configuration settings like Views, Forms, AutoArchive settings and Rules and Alerts.

The pst-file is also known as Personal Folders and Outlook Data File and is able to store several mail, contacts, journal, notes and calendar folders.

Mail folders are the Inbox, Junk E-mail, Outbox, Send Items and Drafts folders.

There is also a folder called Deleted Items. This folder holds all items (even which aren’t mail items) when they get deleted. When a folder gets deleted it will show up as a subfolder of the Deleted Items folder. Emptying the Deleted Items folder will permanently delete all the items and subfolders from the Deleted Items folder.

By default it is located in;
C:\Documents and Settings\%username%\Local Settings\Application Data\Microsoft\Outlook\
For Windows Vista the default is;
C:\Users\%username%\AppData\Local\Microsoft\Outlook\

You should not connect to a pst-file located on a network share as this method is not recommended by Microsoft as the chances for corruption and data loss are a lot higher than when stored locally.

When a pst-file gets corrupted you can use scanpst.exe to search for and fix errors.
The location of scanpst.exe depends on your version of Outlook.
Scanpst.exe cannot fix all type of corruptions of a pst-file. When a pst-file is too badly corrupted you can then try repairing or salvage recoverable items via a 3rd party recovery tool such as Advanced Outlook Repair (discount code DNC-PUXB-HT).

An Outlook 97 – 2002 pst-file uses the ANSI format and can become up to 2GB.
Outlook 2003 and later uses the new UNICODE format for the pst-file and can become up to 20GB and even larger by configuring its maximum size in the registry.

When deleting a lot of data at once from a pst-file, its size on the disk will not directly reflect this. Outlook will shrink the pst-file automatically when the computer is idle. To have Outlook directly return the empty space within the pst-file to your disk, you must manually compact the pst-file.

Copying a pst-file can only be done when Outlook is closed. If you close Outlook and you still cannot copy the pst-file, you might have a shutdown issue with Outlook.

You can back-up a pst-file to a CD-ROM or DVD. To read it’s contents you first need to copy it back to your hard disk and remove the "Read Only" file property as Outlook needs Read and Write access to the file. For complete backup and restore instructions click here.