Outlook 2003 Autocomplete List Migration
You got a new computer and your Outlook 2003 no longer automatically completes the email address that you type in the To: line.
The autocomplete cache is stored in a file called Outlook.nk2
It is located here on your computer:
c:Documents and Settingsyour-profile-nameApplication DataMicrosoftOutlook
Locate this file on your old computer and copy it to the same path on your new computer.
Note that in some cases the file will be named something other than Outlook.nk2 but it will still have the .nk2 extension. When you copy the file to your new computer, rename it to match the name of the existing file.
You can delete an entry from the autocomplete list by pressing the delete key on your keyboard as the entry appears.