All of your Outlook data is compressed into a single physical file with a PST extension. Use Find/Search on your old computer to locate your PST(s) then copy them to a separate folder on your new machine. Be sure to include the hidden folders in your search. Then start Outlook on the new machine and click File>Open>Outlook Data File and navigate to your old PST(s). Once you do that, you can set an old PST as your default delivery location and just keep using all your old data as before.
The PFBackup Utility can be used to copy/backup all your PSTs in one go.
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