All Products Community Forum

An upgrade a couple of years ago resulted in the top-listed reminders having a dark blue background that making it unreadable. I have been told by Tbird support that 'this is a known issue' but, after many upgrades since, it has not been fixed.

Much thanks in advance for any suggestions for fixing this.

Hi,

I try to subscribe to online calendar (.ics format), for example the calendar of the school of my child: webcal://outlook.office365.com/owa/calendar/e9d7c3e1627c47dbbb494c04dd439cb6@montessoricollege.nl/90ee10a5ac224fa2af7e51cd8be5a46215938853368348660489/calendar.ics

But no matter what I try Thunderbird always returns there's no calendar in that particular location. When I try to subscribe to the same calendar in Google (online) it works fine and I can see all content.

This is just an example. This problem occurs with virtually all calendars I try to add in Thunderbird.

Has anyone a solution for this problem? Thanks

Hello, In Tbird 145, my calendar does not show the column header for the weekday 'Friday'. All six other headers are displaying correctly. This is also occurring when 'Workweek days only' is selected. Thank you.

I'm trying to sync Thunderbird Calendar with iCloud. Every time I enter the password generated by iCloud, Thunderbird indicates that the credentials are incorrect. Any suggestions?

Hi, I was running Thunderbird on windows 10 before I had to do a system reset, so all software has been wiped out from the disk. After reinstalling thunderbird I wanted to recover the previous calendars, so I copied the backed up files within the 'calendar-data' directory to the calendar-data directory in the new install and moved the new files in a directory. (see attached image) Before doing this I had already created some new calendars in the new installation.

Nevertheless, despite the files have been moved and the older ones substituted them, I keep seeing the newly created calendars but NOT the older ones (which are the ones that interest me) and I believe I should not see the newly created ones. Why is this happening? Why is Thunderbird still showing me the new calendas when the files aren't accessible anymore??? Regards

I am running Thunderbird 141 on Windows 11. When I open the task tab, it says: "Please select a calendar that supports tasks". I have tasks on two gmail accounts. But it wont let me select either of them (or my other account).

How can I set the calendar to completely show on the screen - currently in Full Screen mode half of Sunday is off the screen, including the settings icon next to Day/Week/Multiweek/Month. My monitor is a 19" diagonal 4:3 - not a widescreen 16:9. For what it's worth the mail screen displays fine

Thanks, Marc

That’s not a new bug for me, I’ve been dealing with this one for a few years new, across multiple PCs and Thunderbird installations: from time to time, some of my appointments disappear from Thunderbird calendar. Forcing a synchronization achieves nothing: the appointments are correctly available on google calendar and are missing from Thunderbird.

From time to time I need to unsubscribe from the google calendar, re-subscribe and for a few days everything is fine. Then appointments start to disappear again… rinse and repeat.

Now, I understand it’s impossible to point out what’s going with so little details, and in fact my question really is: what can I do on my side to identify the root cause of this? Are there error logs I can check or other clues that can help with that?

Ich bekomme ständig folgende Aufforderung: Authentifizierung erforderlich - Mozilla Thunderbird https://spica.t-online.de verlangt einen Benutzernamen und ein Passwort.

I have calendars and tasks enabled in Roundcube on an account on a cPanel VPS, and I can create a calendar synced to the CalDAV calendar there, but I can’t sync tasks. When I select the calendar on the Calendar tab in TB, at the bottom of the task pane it says “Please select a calendar that supports tasks. I can create both events and tasks in Roundcube. When I create a calendar in TB there is no point at which I can chose whether to sync events or tasks or both. I’m running 143 on Win11. Please help.

I REALLY LIKE THE THUNDERBIRD EMAIL AND CALENDAR. i HAVE GOOGLE AND GEMINI ON MY CELL PHONE AND REALLY HATE AND IT SEEMS LIKE EVERY DAY OR SO THEY ARE ADDING SOME OTHER "ROAD BLOCK" NOT GOOD FOR A 79 OLD LADY TO HAVE THIS KIND OF STRESS "AS WE SAY "JUST KEEP IT SIMPLE "!! DO I NEED SOME ATTACHMENT TO BLOCK GOOGLE AND GEMINI AND JUST STAY WITH MOZILLA - THUNDERBIRD AND ALL THE PROGRAMS THAT I LOVE BECAUSE THEY JUST WORK AND NOT STRESS ME OUT!! THANKS FOR ANY CLUES OR ASSISTANCE YOU CAN GIVE ME. LINDA

An old forum describes how to sync calendars in Thunderbird. Here is an easy solution - In the left-hand pane of your calendar page, right-click your calendar name/ export calendar - into a removable device. In your other computer - Tools/import/ import from a file/ choose to import calendar - easy!

Hi, I really need Calendar function as part of my email client, I have loved Lightning and it has worked well for meeting requests, I used it for confirmation of photographic shoots. Getting the confirmation meat the the client had the same information as the appointment in my Calendar. Lightning is so important that I believe it should be the default calendar for TB and be built into every update. How long before I can use it again, please?

When moving a task from "meine Aufgaben" (my tasks) to another Gmail calendar tasklist ("AI"), a ghost entry, which cannot be completed or deleted, remains in the old Thunderbird tasklist "meine Aufgaben". Thus I have many tasks twice in different Thunderbird-calendars, but only once in Gmail.

Hey all,

For about half of the notifications I get from my google calendar, I get a dialogue warning me that the item has changed on the server and I can submit my changes anyway or discard and reload. It doesn't matter what I choose - the pop up goes away and reappears at the next notification.

I have searched for other reports of this issue and seen it reported many times in the last few years. I have tried all of the known solutions but none of them seem to fix the issue for me.

Here's what I've tried:

- Unsubscribed and resubscribed to the google calendar - Unsubscribed, shut down Thunderbird, deleted the calendar-data folder from my profile, opened Thunderbird, and resubscribed to the google calendar - Toggled "Read Only" every which way - Toggled "Offline Support" every which way - Turned off show reminders (which fixes it of course but I want reminders, that's the problem) - Deleted the offending events in my google calendar and recreated them from scratch - which has returned the same "item changed on server" warning.

I don't know what else to do at this point. I don't see any new reports of this issue so am I just missing something fundamental here? Do people not use google calendar in Thunderbird? Is it known to not work if you have an iPhone that also shows calendar notifications or something?

My desktop specs are Windows 11, everything at latest, no additional calendars other than "Holidays in the United States" (which I think comes with Thunderbird), and the BorderColors D extension to change colors of my email border depending on which address I'm sending from.