And in addition the upload funtion for files didn't worked for me as I created the question (and the account). Therefore I add it here.

re :I tried to delete abook.mab and history.mab,

What do you currently see in your 'profile name' folder? In Thunderbird

• 'Help' > 'Troubleshooting Information'
• click on 'Open folder' button

A new window opens showing the contents of your 'Profile name' folder. Click on the 'Type' column header to sort by type. This will put all the MAB files together. Post an image showing all the .mab files that currently exist in the 'profile name' folder.

Thanks for your quick response!

I can see only the two expected mab-files. Some old ones are renamed to .old and shall not disturb!?

This is unusual. I notice that you do not use the default location to store all the files and folders that are usually in the 'profile name' folder.

Instead of this location: C:\Users\<Windows user name>\AppData\Roaming\Thunderbird\Profiles\<Profile name> folder

you are using: Dieser PC\Crypted (D:)\Thunderbird-daten

What do you see in : C:\Users\<Windows user name>\AppData\Roaming\Thunderbird\Profiles folder ? Do you see 'profile name' folders?

Please access: C:\Users\<Windows user name>\AppData\Roaming\Thunderbird folder Open the 'profiles.ini' file using a text editor like 'notepad'. Please post an image showing contents.

Thinking out aloud here.....For some unknown reason, it would seem that you have the correct address books from the location you are currently using as storage, but also are seeing same default mab files from a default profile name. I'm wondering if this has something to do with the 'All Address Books' which is a virtual address book.

In 'Address Book' If you right click on the first 'Personal Address Book', is 'delete' available ? Are there any contacts in that address book?

If you right click on the second 'Personal Address Book', is 'delete' available ? Are there any contacts in that second address book?

I'm trying to ascertain if one of those address books is the true default.

Do you know when the two copies of default Address Books appeared ? Did they appear when you moved your profile storage or when an update occurred?

What version of Thunderbird are you currently using?

Indeed, I use a different location because I have to store my emails on an encrypted partition... In C:\Users\<Windows user name>\AppData\Roaming\Thunderbird\Profiles folder is an profile as you see in the picture, but it contains only a directory named "pepmda"

The profiles.ini has the content:

[General] StartWithLastProfile=1

[Profile0] Name=crypt IsRelative=0 Path=D:\Thunderbird-daten Default=1

All 4 adressbooks have entries in them; the two personal addressbooks have the same and the two all addresses have the same entries. When I delete an entry in one addressbook, it is also deleted in the other. So it is clear, that it is only a link to the same adrressbook.

As far as I knew I had the duplicated entries before I moved to the other storage place.

My version of Thunderbird is 60.5.1 (32 Bit)...

to go right back to the start here.

All address books is a virtual address book that displays the contents of all other address books.

Abook.mab and history.mab are default address books and if you delete them and restart Thunderbird they will be recreated as they form part of your default profile

Hello! I found the solution: I checked a thunderbird prefs.js at another comuter and I saw, that there were less entries containing "adress":

I deleted all entries starting with "lap_2.servers" except the two ones I found on the other computer: ...history.description and ...pab.description

After a restart of thunderbird the mirror entries are gone... I hope this helps other with the same problem...

I do not know, where these entries came from. Perhaps from an import of the adressbooks or maybe by an sync-process to syncronize the adressbooks over multiple computers?

Nevertheless, thank you for your help!!!

Hello Toad-Hall! Our last posts overlapped... Earlier I tried to delete both .mab files as you mentioned and thunderbird created two new ones; in thunderbird the mirror adressbooks were still there! (But then without entries...) So only to delete the adressbook-files doesn't helped with my problem. THe solution was to delete the wrong entries in the configuration...