The .pst file is a format used by Lotus Notes archives and Microsoft Outlook for Windows. .olm is the format used by Outlook for Mac. To import a .pst or .olm file to Outlook for Mac 2011, it will first need to reside on your Mac’s file system. If you have stored it on a USB thumb drive or a DVD, use Finder to drag it onto your Mac desktop.
- From Finder, open Microsoft Outlook by clicking Applications, Microsoft Office 2011, Microsoft Outlook.

- From Outlook, select File, Import.
From the Begin Import box, click the radio button next to Outlook Data File (.pst or .olm), and click the right arrow to continue.

- Select the type of file you wish to import and click the right arrow to continue.

- Choose the file to be imported and click Import.

- When done, you’ll see the following. Just click Done. Your .pst or .olm file has been imported into your Outlook for Mac 2011 client.

Other resources:
- See posts tagged with Office 2011 Mac (and posts tagged with Office 2010)
- See article from PCWorld Business Center Office for Mac 2011: Outlook FAQ
- See article from Macworld Magazine Office 2011: Excel FAQ
- See the Microsoft website for Self-Help and Video Tutorials: Office for Mac 2011 How-To
- See the Microsoft website for What’s New: Office for Mac 2011