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In Courier click on one of your mailing lists and highlight all addresses in the right panel. Right click in the highlighted area and export you mailing list to 'Bulk Mail File' on your desktop. Open the Thunderbird address book. Go to TOOLS/IMPORT/ADDRESS BOOK/TEXT FILE. To see the text files change the files types to 'all files' and chose your bulk mail file. Choose only the email address to import. You will get a new address book with the name of your file. Now highlight your Personal Address Book and press the