Open Outlook
On the File menu, click Import And Export. If the command is not available, rest the pointer over the chevrons at the bottom of the menu, and then click Import and Export
Click Import from another program or file, and then click Next
Click Personal Folder File (.pst), and then click Next
Type the path and the name of the .pst file that you want to import, and then click Next
Select the folder that you want to import. To import everything in the .pst file, select the top of the hierarchy
Click Finish