Diễn đàn hỗ trợ Thunderbird

I use Thunderbird 159.0 (64-Bit), german version, on Windows 11. I have integrated as well 2 local calendars as well as 3 calendars maintained on my synology disk station. Today I have noticed that Thunderbird Calendar does not work anymore: I do not see my calendars (the calendar sheet is empty) and the tool does not react neither on the calendar options (the three dots ...) nor on add calendar ("Kalender hinzufügen"). Is it possible to reset or de-installate the calendar tool? Or to delete an re-add the calendars?

(The calendars on my disk stations work fine on the disk station and are still accessible with Android Business Calender.)

The release notes for TB 159.0 indicate that MS Exchange calendars are now automatically detected. I have tried deleting my old EWS MS Exchange email account, and adding it back in using the Graph option. Email is working just fine, but no calendar was detected. Can anyone offer some assistance? Much appreciated!

Lyle

My Thunderbird installation (159.0/Windows11) has evidently just updated, and my Calendar tab is suddenly a complete blank space. There's a support article here that appears to discuss exactly this situation, and gives precise steps for getting into "Config Editor" in Advanced Settings, entering a long search string, and issuing a Reset command. (Mail and contacts are just fine.)

Which I tried...

But there is no "Config Editor" button in the dialog I get when clicking Advanced Settings at the bottom of the Settings tab, only a mostly blank screen with no list of settings and a dialog box in which one can enter text (with options for "Boolean", "Number" and "String"). And entering the search string given in the support article produces, with a bit of finagling, a toggle that will change its setting from True to False and back again (and a trash-bin icon that offers to delete it), but neither "True" nor "False" produces any instance of a "Lightning" extension in my list of extensions (which is short and uncomplicated), so (a) I can't delete the extension as instructed, because it's not there, and (b) restarting Thunderbird only continues to give me the unhelpfully blank Calendar tab. (And I do mean "blank" here - there isn't even an empty calendar grid on that tab at this point.)

I *think* the article is probably right that my data is still there (I can see .ics files with current dates in File Explorer), but at this point I can't get at it and can't seem to get the interface unstuck.

Device name cY9maT-2cx7dixc Processor AMD Ryzen 7 5700U with Radeon Graphics (1.80 GHz) Installed RAM 32.0 GB (27.9 GB usable) Graphics card AMD Radeon(TM) Graphics (4 GB) Storage 142 GB of 932 GB used Device ID CE037C95-0762-435F-A4DD-CAB5A50CDBDF Product ID 00330-54188-55022-AAOEM System type 64-bit operating system, x64-based processor Pen and touch Pen support

My calnedar is frozen. On the left side is the month of October 2026. I click on the arrow to move to Novemebr or September nothing happens. I can not enter new reminders in any date due to no dates appear. In the centre and to the right. I have a white screen. No dates. My calendar is set for Weekly. At the top menu bar i see "events in Next 7 days" and the menu bar shows "Title Start End Category" below this menu bar is a white screen. What have I done to create this situation ans what do I do to fix it (get my weekly calendat back nd be able to enter reminders).

I want to connect Thunderbird to an Office 365 calendar. All of the help files I've found point me to TBSync, but when I try to get that using the Add-ons manager it says that it's not supported in version 159. Is there another approach I can use? Thanks!

I have added a subscribed calendar to Thunderbird using an URL. It is a public calendar. It shows in my calendar when added, When I exist and come back to Thunderbird later, the calendar still shows in the list but all of the appointments/events are missing. It I remove the calendar and re-add, still no appointments/events. A new install of Thunderbird produces the same results.

I am early days learning to use Desktop Thundermail Calendars in Windows 11. I have several calendars showing up in my list of Calendars. Home, My name (seems to draw input from 2 emails I have connected), New Holiday, Thundermail Calendar, My wife's name (seems to draw input from 2 emails I have connected that she wants me to monitor as she rarely uses them). I would like to get a basic explanation of what each of these calendars are and how they may relate to each other. This may already exist somewhere? For example: what is the difference between Home and Thundermail Calendars? Why do my 2 other emails only form one combined calendar?

I love TB and I've been using it for a long time, but it has 1 very annoying habit. The Calendar reminders window repeatedly comes to the foreground and takes keyboard focus. It happens frequently and most annoyingly while I’m while I’m composing an email.

The interruptions happen too frequently. Is there a way to prevent to reminders window from coming to the foreground or at least reduce the frequency?

I'm using TB 153.5.1esr (64-bit) on Windows, but this has been occurring for years. I can't believe others aren't experiencing the same annoying behavior.

Since Thunderbird Meadow the calendar in broken in dark mode. If one tries to edit an entry, one is greeted with black letters on black background. Prior to this it was at least in white letters and changed to black in light mode. Wonder when this will be corrected??

Bonjour très interressé pour sauter de google a mozilla existe il Thunderbird agenda tache comme sur windows existe il l equivalent sur android sinon est ce prévu et pour quand? Bonne journee

I'm not sure if this is a right place to ask, but since calendars are on Thunderbird page I guess it is. I downloaded a calendar from https://www.thunderbird.net/uk/calendar/holidays/ for Ukraine (direct link -- https://www.thunderbird.net/media/caldata/autogen/UkraineHolidays.ics) and it doesn't contain any holiday. I did that from my Nextcloud server and directly from browser -- both times result is the same.

I have my Google Calendar added through the network/gmail account process. I can see the events from my Google cal in TBird. When I accept an invite that came into my email in TB, it gets added to the TB calendar but never syncs back to my Google cal. Looking at the Error Console, I keep getting "Server Replied with 500"' errors (full error code is below).

I already tried all the online steps - delete/add calendar, clear password, reset OAuth token, still get the same issue.

calendar: [calCachedCalendar] Unable to perform playback action add to the server, will try again next time (longnumbersequence,[Exception... "Server Replied with 500" nsresult: "0x80040111 (NS_ERROR_NOT_AVAILABLE)" location: "JS frame :: resource:///modules/CalDavCalendar.sys.mjs :: onOperationComplete :: line 580" data: no]) CalCachedCalendar.sys.mjs:570:20

Hi Despite I make reminders (I get the bell symbol for the event) for events in calendar, I don't receive alarms any more. If I have Thunderbird open at the time for the alarm, I might get an alarm. If I then postpone the event I don't receive the new alarm. I have had Thunderbird and calendar for several years and it has worked without any problems, I would receive alarms occured for the time I didn't have Thunderbird open, when I opened Thunderbird. I did get the alarms, also when I postponed an event. But for long it hasn't worked. I can't rely on the calendar not receiving alarms/reminders. I have tried to delete/remove Thunderbird and install again, that didn't help. I hope someone can help me, please. Answers in Danish are welcome. Best Joyanna

when I add to or make changes to thunderbird calendar on my desktop, it does not copy to my laptop. they are on the same network. can they both sync to new changes?

i have several calendars one being Home, RBSALES, BIRTHDAYS can I set one of these to be the default? right now the default is HOME which as far as I know I do not use it. If all my event are in RBSALES can I delete the HOME calendar? Thank you, Rick

Hi,

Thunderbird regularly unable to connect to my Google Calendar. Is there anything I can do? I updated it to the latest version today and now it said all the calendars (local, Google) are unavailable no matter what I do (unsubscribe, subscribe again and again)

And if I try to create a new calendar, the Google Calendar option is not even there anymore.

Is the latest Thunderbird broken or something I did?

Thanks,

Will