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Calendar entries disappear after updating from v78 to v91.

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  • Last reply by sciclunt

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I updated Thunderbird from 'Help - About Thunderbird' from v 78 to v 91. I had one calendar and after the update all entries in the calendar disappeared. I removed v91 and installed v78, and restored my last backup of the profile to solve the issue. Now I am on v 78.12.0 and I may update to v 78.14.0 from 'Help - About Thunderbird'. Is this a known issue?

I noticed that on v 78.12.0, the Calendar Properties shows 'Location: moz-storage-calendar://'. If I'm not mistaken the 'Location' field was removed in v 78.14.0.

I updated Thunderbird from 'Help - About Thunderbird' from v 78 to v 91. I had one calendar and after the update all entries in the calendar disappeared. I removed v91 and installed v78, and restored my last backup of the profile to solve the issue. Now I am on v 78.12.0 and I may update to v 78.14.0 from 'Help - About Thunderbird'. Is this a known issue? I noticed that on v 78.12.0, the Calendar Properties shows 'Location: moz-storage-calendar://'. If I'm not mistaken the 'Location' field was removed in v 78.14.0.

Chosen solution

Thanks Lampros for your help. I wanted to avoid deleting the profile because I will loose all settings, so I tried the following shortcut and it worked: Export calendar - Update to v 91 - Exit TB - Delete all files in folder calendar-data from the profile - Launch TB and import calendar.

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Before upgrading to TB91.


Uninstall old version of TB. I would also suggest to delete the profile folder (export contacts & calendars) Install TB91 ( Create a new profile) Import calendars.

Modified by Lampros

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Chosen Solution

Thanks Lampros for your help. I wanted to avoid deleting the profile because I will loose all settings, so I tried the following shortcut and it worked: Export calendar - Update to v 91 - Exit TB - Delete all files in folder calendar-data from the profile - Launch TB and import calendar.