Forum zhromadźenstwa Thunderbird

I am using Windows 10 Enterprise LTSC, Version 21H2, and Mozilla Thunderbird 140.3.1esr (64-Bit)

Suddenly, the number of entries in my address book has shrunk to 259. The size of the file abook.sqlite was 768 kB. Following the advice on https://support.mozilla.org/en-US/kb/rebuilding-global-database, I did Rebuilding the Global Database That did not have an effect on my address book, the lost email addresses did not reappear. What can I do?

Matthias (now to this forum)

I run aPC with Win 7 (64 bit) and use TB 115.18.0 (64 bit) Supernova (esr) I have all my contacts in a folder on the HDD (data drive). However, I cannot find where TB stores its "contacts" folder. Nor how to import my contacts from the windows folder. I have tried to download a "contacts sidebar" from TB, but my ver. of TB is "not suitable" " " " " create a "contacts" folder to replace the "Starred" folder etc. (failed) and even created a "contacts" folder in the "Local Folders"(succeeded). However when I tried to drag and drop the files from windows toTB, it failed.

There must be a simple way to to import contacts. 

Can somebody help please.

John