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Thunderbird calendar stuck in AM/PM time although System is in 24h

  • 3 replies
  • 2 have this problem
  • 1 view
  • Last reply by mrt3

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Hello there,

im using Thunderbird and its Calendar for years. Recently moved to a new Computer and made a fresh account. Now the Calendar is displaying only in AM/PM Format. I read some articles stating that it mirrors the systems timesettings, but those are 24h. What makes this particularly annoying is that if i open a date it will give me the 24h option only. When this date is saved it will then translate falseley into AM/PM which makes my calendar useless... (eg. 19:00 is translated to 10:00 (dont know if am or pm))

What can I do to fix this issue? Would love to continue using Thunderbird Calendar.

btw. im on Win 10. Using my Calendar mainly in combination with Google Calendar. Already tried with just provider for google calendar activated and lightning as well activated. same result.

Hello there, im using Thunderbird and its Calendar for years. Recently moved to a new Computer and made a fresh account. Now the Calendar is displaying only in AM/PM Format. I read some articles stating that it mirrors the systems timesettings, but those are 24h. What makes this particularly annoying is that if i open a date it will give me the 24h option only. When this date is saved it will then translate falseley into AM/PM which makes my calendar useless... (eg. 19:00 is translated to 10:00 (dont know if am or pm)) What can I do to fix this issue? Would love to continue using Thunderbird Calendar. btw. im on Win 10. Using my Calendar mainly in combination with Google Calendar. Already tried with just provider for google calendar activated and lightning as well activated. same result.

Chosen solution

Hey Matt, Thanks for your quick reply. The google calendar displays in 24h. I use it also on my phone and on my Laptop with Thunderbird (where it is working properly). So the problem has to be somewhere within this local Thunderbird installation.

OK... I removed the Lightning Addon completely (it was just deactivated before) And now it seems to work. Just when I was about to make screenshots of how its still not working XD hehehe

Thanks for your Help!

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All Replies (3)

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I use the latest Thunderbird 78.11.0 (64-Bit)

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There is no lightning for V78. If you have managed to get one, it is probably malware!

There is a built in calendar.

You might find something useful here http://kb.mozillazine.org/Date_display_format

Or it might be if you are using a google calendar they the web version is not set to display a 24hour clock.

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Chosen Solution

Hey Matt, Thanks for your quick reply. The google calendar displays in 24h. I use it also on my phone and on my Laptop with Thunderbird (where it is working properly). So the problem has to be somewhere within this local Thunderbird installation.

OK... I removed the Lightning Addon completely (it was just deactivated before) And now it seems to work. Just when I was about to make screenshots of how its still not working XD hehehe

Thanks for your Help!