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Thunderbird Calendar - Data disappeared but calendar still operational

  • 1 reply
  • 1 has this problem
  • 8 views
  • Last reply by mattrayner

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Hi There, My Thunderbird calendar data has suddenly disappeared. Thunderbird version 78.14.0. Installed 17/11/16 and last updated 09/09/21. Set up on a Macbook Pro using macOS Sierra 10.12

Whilst using my calendar on Thunderbird yesterday I was editing an event, the edit didn't save properly and reverted to the original event data. This repeated on the 2nd attempt at editing the event, and then some of the calendar data disappeared. The next minute all the calendar data disappeared.

I have a number of calendars set up within thunderbird, and these are all still listed (with their colours) in the task bar on the left. But the actual calendar data is gone. The function to create an event still works - but when I save the event it does not appear. All the calendars are 'unhidden' See attached screenshot.

I used to use the lightning extension, however I believe with this version of thunderbird the calendar is integrated with no add on/extension. I have checked the add-on section and nothing is showing.

Any help is appreciated as I run my life (and various businesses and projects) through my thunderbird calendar, and am currently stuck. Please note I am not too familiar with the back-end of a mac, so any instructions to access thunderbird files would be helped with an explanation of where they can be located on a mac.

Many thanks

Hi There, My Thunderbird calendar data has suddenly disappeared. Thunderbird version 78.14.0. Installed 17/11/16 and last updated 09/09/21. Set up on a Macbook Pro using macOS Sierra 10.12 Whilst using my calendar on Thunderbird yesterday I was editing an event, the edit didn't save properly and reverted to the original event data. This repeated on the 2nd attempt at editing the event, and then some of the calendar data disappeared. The next minute all the calendar data disappeared. I have a number of calendars set up within thunderbird, and these are all still listed (with their colours) in the task bar on the left. But the actual calendar data is gone. The function to create an event still works - but when I save the event it does not appear. All the calendars are 'unhidden' See attached screenshot. I used to use the lightning extension, however I believe with this version of thunderbird the calendar is integrated with no add on/extension. I have checked the add-on section and nothing is showing. Any help is appreciated as I run my life (and various businesses and projects) through my thunderbird calendar, and am currently stuck. Please note I am not too familiar with the back-end of a mac, so any instructions to access thunderbird files would be helped with an explanation of where they can be located on a mac. Many thanks

All Replies (1)

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Next day Update: Located the calendar-data file in the thunderbird profile: local.sqlite It appears that the calendar data is still in there. The 'modified' and 'last opened' for this file is the date/time that this issue happened (18:36 25/10/21)

There is also another file: deleted.sqlite This shows 'modified' at (18:33 25/10/21) and 'last opened' as (just now) when I last opened TB

There is a futher file: local.sqlite-wal (write-ahead-log) This shows 'modified' and 'last opened' as (just now) when I last opened TB.

I have tried a couple of other suggested fixes on moz support for similar calendar data issues (although not exactly same), to no avail.

My guess is TB has some interruption/loss in the path to my calendar-data. Can anyone help please?

Many thanks