Backup and Restore Outlook Data

 

• Go to your Outlook folder in Windows Explorer.
• Highlight all files ending in ".pst".
  • Make sure in particular your selection includes "outlook.pst" and "archive.pst". [1]

• Select File | Import and Export... from the menu in Outlook.
• Select Import from another program or file.
• Click Next.
• Highlight Personal Folder File (PST).
• Click Next again.
• Now use the Browse button to select the backup copy of the PST file you want to recover from your backup location.
• Make sure Replace duplicates with items imported is selected.
• Click Next.
• Finish the import process with Finish.

Usually, the default import settings work fine, but you may want to tweak them to suit your needs. [2]

Reference
[1] http://email.about.com/od/outlooktips/qt/Back_Up_or_Copy_Outlook_Data.htm
[2] http://email.about.com/od/outlooktips/qt/Restore_Outlook_Mail_Contacts_and_Other_Data_from_a_Backup.htm