Splitting a ThunderBird address book


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Question: I have one address book with over 1000 entries (several hundred duplicates) from one list being updated several times (I need to retain the old listings for historical purposes).

How can I split an existing Thunderbird address book into two address books? The scrubber program balks at 1000 entries and I need to cut the book into two or three pieces.

(I imported these lists from Eudora where it wasn't a problem keeping them separate; Thunderbird seems to want to lump them all together.)


EQ Admin

EQ Forum Admin
Staff member
Hi Chip,

In Mozilla Thunderbird you can go into the address book and then the Tools -> Export menu to get a version to work with. Export your address book to a comma separated csv file. You can then use Microsoft Excel to work with the csv file and break it up into multiple csv files. If you do not have Microsoft Office you can download a free version called Open Office that will have the same functionality. Make sure you keep the same formatting within the csv files. When you are done you can go back into your address book and use the Tools -> Import menu to pull the data back into Mozilla Thunderbird.

:welcome: Welcome to Email Questions! -Raymond