Please provide more context info about how this started to happen. Is this an account that was working before? Did it stop working while Thunderbird was running or did something relevant happen since the last time you used Thunderbird that could be related? Your <i>Inbox</i> shouldn't become empty just because Thunderbird cannot connect to the server. It should simply show what was there the last time it could successfully connect. It looks as if you were using a different profile now… Check the following article in case it could be relevant to you: https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-thunderbird-update