Hi all,
I need to import my old emails stored in an MBOX file, but the import option is greyed out in Thunderbird. I installed ImportExportTools NG, but nothing happens. Restarting Thunderbird, reinstalling the add-on, and even trying different versions hasn’t worked. What’s going on?

Instead of dealing with this mess, I used SysTools Thunderbird Import Wizard, and it worked instantly. If you’re facing the same issue, check this tool to import MBOX to Thunderbird. Any manual fixes that actually work?

Solution Found: https://www.systoolsgroup.com/thunderbird-importer/