I recently migrated Thunderbird from my old Windows 10 computer to my new Windows 11 computer. I seem to have resolved all my issues with Thunderbird except for the following: In the Calendar, I have all my events from 2014 forward until the end of May 2024. After that time period I only have 2 events, when I know for a fact that I had many more. I would like to recover this data for historical purposes because it contains many medical appointments. Does anyone have any ideas about how this can be accomplished?