Thundebird keeps showing pop-up errors about a long index file path

I have over 200 email accounts in Thunderbird, and I am getting constant pop-up error messages that say: "Не удалось открыть индексный файл для 'Входящие на [email]'. Возможно, произошла ошибка на диске или полный путь превышает допустимую длину." I don't need help fixing the emails themselves, but I need to permanently disable these pop-up alert windows because I will soon have over 2000 accounts and I don't want 2000 errors popping up. I am using the latest version of Thunderbird. I have tried looking for "about:config" or the "Navigation Toolbar" to change the settings to "false", but my interface is heavily customized and I cannot find the menu or the address bar. I need a step-by-step guide on how to disable these error alerts, preferably using the Windows Registry or a configuration file if the menu is hidden.