Thunderbird Community Forum

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!

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.

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?

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??

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?

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

if I start Tunderbird I get the message "https://caldav.web.de verlangt einen Benutzernamen und ein Passwort". I have stored the password many times but it appears any time I start Thunderbird

Hi everyone. I have setup Synology Calendar on my NAS, and I am now able to Sync my calendar across multiple devices. While events in calendar sync, I am unable to create tasks that will sync to all devices, and have the "Please select a calendar that supports tasks" at the bottom of the panel on my calendar panel.

I see there is discussions for this same situation, but for syncing Google accounts.

Does anyone know if I can do this in Thunderbird or do I just live with events working?

TIA.

I successfully linked / synced the thunderbird calendar with the iCloud calendar. Calendar entries manually entered in iCloud or iPhone calendar are successfully synced and are visible in the thunderbird mail. The other way round, syncing the existing entries in the Thunderbird calendar does not work. They do not appear in the iCloud or iPhone calendar. Searching the internet, the specific Thunderbird or Apple help-sites did not provide an obvious solution for this problem. I went through all (or nearly all) recommendations given by Apple, no success to sync from Thunderbird to iCloud.

Any suggestion what to modify or adjust

jm

I have upgraded to TB153.0.3ESR. I've been on the ESR stream for a long time now. But recently, I started having trouble with my google calendar appearing. I've deleted the provider plugin, I've moved to OAuth2, and for the most part, calendars that I have that are read-only from google show up all the time. But my personal read/write google calendar will not show up.

If I go in and delete the cache.sqlite file, and then start Thunderbird, my entries show up. However, if I switch to a different week, my read-only calendars still show up, but my personal calendar goes away.

I've tried everything listed in all of the steps to fix this, but I can't find anything that gives a clue as to what is happening. Anyone else see this?

Steve.

Little thing. None of the sections seemed appropriate. Win 11 153.0.3 (64-bit) In the left-hand panel of Calendar the top left icon of the actual calendar day/week/month matrix is supposed to take you to today (though it's not obvious by the icon which changed a few versions back). When first coming to it after a restart (hibernation mostly in my case) it doesn't move the highlighted day. I have to click first on any other day, then click the icon for it to go to today.