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How to merge duplicate contacts & lists

  • 3 replies
  • 1 has this problem
  • 32 views
  • Last reply by heartycat2

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I have a large address book of over 1800 emails. Many of them have additional details (mailing addresses, phone numbers, etc). Duplicates frequently appear because Thunderbird inserts contacts into the address book when I send a reply, even if the address already exists.

The add-on Duplicate Contacts Manager has not been updated for years, and it was not designed to merge contacts. It simply deleted one or the other, without retaining the additional details.

Also, when there is a contact list in the address book, it is not sufficient simply to delete duplicates. If contact A and B are duplicates, with contact A in list X and contact B in list Y, then a merger should involve inserting all fields from contact B into A, then adding new A to list Y.

It will get more complicated if the email address is the primary email in contact A and the additional email in contact B. This hierarchy must be preserved in the merging.

Does anybody have a way to do this? It doesn't appear to be a native Thunderbird option, and no add-ons exist.

I have a large address book of over 1800 emails. Many of them have additional details (mailing addresses, phone numbers, etc). Duplicates frequently appear because Thunderbird inserts contacts into the address book when I send a reply, even if the address already exists. The add-on Duplicate Contacts Manager has not been updated for years, and it was not designed to merge contacts. It simply deleted one or the other, without retaining the additional details. Also, when there is a contact list in the address book, it is not sufficient simply to delete duplicates. If contact A and B are duplicates, with contact A in list X and contact B in list Y, then a merger should involve inserting all fields from contact B into A, then adding new A to list Y. It will get more complicated if the email address is the primary email in contact A and the additional email in contact B. This hierarchy must be preserved in the merging. Does anybody have a way to do this? It doesn't appear to be a native Thunderbird option, and no add-ons exist.

All Replies (3)

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Personally if I were in your situation I'd tackle it manually: as you say, there are no functions in Thunderbird and no add-ons to do it. So I'd export the data as a csv file into a spreadsheet; sort the spreadsheet so that all the entries for the same contact are grouped together (e.g. by surname); manually copy-and-paste the data from those entries into a single record; delete the other records for that contact; and then import the csv file into Thunderbird again. Also I would turn off the function that automatically collects every address you write to, since it clutters up the address book with redundant information!

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Not sure that will help me. I have same information in both address file and list, but it continues to duplicate or delete files. I have worked and worked on this, but it continues.

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I am having the same problem I believe. I have a mailing list and every time I add a name from the master file list, it either duplicates it 2-10 times or it doesn't even make the entry. I am at a loss. There are about 60 contacts and this shouldn't be too many to put into a list. I have tried everything, including deleting and starting again. I get down to the last few and it starts doing the duplications, deletions, and not adding them. AAAAgh!