If you are trying to recover an icedove or thunderbird address book from backups,
backup and then export to *.LDIF at least one of you default address books
( 'Personal Address Book'(abook.mab) and 'Collected Addresses'(history.mab) )
You will find the abook.mab and history.mab files in ~/.icedove/randomprofilename.default/
or ~/.thunderbird/randomprofilename.default/
If it is a new installation you may skip the step above and just
name the address-book you want to import abook.mab or history.mab,
put the *.mab in an icedove or thunderbird profile
and check it out with
$ icedove --addressbookyou may export it to an *.ldif which can be imported to thunderbird or icedove
if you want to have old and new address-books in one installation you may concatenate old and new *.ldifs and then import them ( hmm, err, I don 't know how it handles duplicates )
... just import *.ldifs as additional address-books
( .mab files are weird -- a classic case of over-complication )
also: http://kb.mozillazine.org/Moving_address_books_between_profiles
Moving address books across icedove or thunderbird profiles or installations