Converting Outlook Express contacts to be used by Outlook is even simpler. In fact, you can import Outlook Express contacts into Outlook without even opening Outlook Express.
Start Microsoft Outlook and go to the File menu from the main Outlook window. Click Import and Export to start the Import and Export Wizard. Select Import Internet Mail and Addresses and click Next.

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Select
Outlook Express from the Outlook Import Tool. Clear the
Import Mail and
Import Rules checkboxes if you only want to convert the contacts to Outlook. Click
Next again.

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Determine whether you want to allow or replace duplicates and click
Finish. If prompted, select the location of your Outlook Express application and click
OK. When the files are converted, a message will appear summarizing the number of contacts imported into Outlook.