An Outlook .pst file contains exported information for an email account, such as messages and attachments, contacts, and calendar information. Instructions here walk you through opening a .pst file so its items are merged into the existing Mailbox's folders, calendar, contacts etc.

NOTE: If you want to open a .pst file as another list of folders instead of merging its data into the existing Outlook folders, see Add Mailbox Content from an Exported .pst File.

1. With Outlook open select the File tab in the upper left, then the Open & Export link and Import/Export.
2. In the Import and Export Wizard select Import from another program or file, then Next.
3. In the next window select Outlook Data File (.pst), then Next. You may need to use the scroll bar on the right to find this option.
4. If Outlook finds a .pst file in a default location it will appear under the File to import field.
   To select another file click Browse to locate the .pst file on your computer (see this FAQ for an important warning regarding network drives and .pst files) that you would like to open. Select Next to continue.
   NOTE: The three options in this window allow you to change what will happen with any duplicate items (email messages, calendar appointments, tasks, etc.) that may exist if you are importing into an existing list of folders. If you are not sure about duplicates, select the second option, Allow duplicates to be created, to be safe.
5. At the next window click on the main folder you would like to import to highlight it. If there is an arrow to its left you can click on it to expand and view any subfolders; check the option to Include subfolders if you wish to import everything under the main folder.
   Make sure the option to Import items into the same folder in: your email address(or your name) is selected at the bottom of the window to merge email messages, tasks, etc. into the same folders of your current Outlook profile. Select Finish.
6. Outlook imports the email, appointments, tasks, etc. into your current profile.