I had to install TBSync and its Exchange provider. After that, everything worked perfectly, including calendar syncing. https://addons.thunderbird.net/en-US/th

I had to install TBSync and its Exchange provider. After that, everything worked perfectly, including calendar syncing. https://addons.thunderbird.net/en-US/thunderbird/addon/tbsync/ https://addons.thunderbird.net/en-US/thunderbird/addon/tbsyn... https://addons.thunderbird.net/en-US/thunderbird/addon/eas-4-tbsync/ https://addons.thunderbird.net/en-US/thunderbird/addon/eas-4...