Hi figallego, I expect you saw the discussion here (sorry it's rather long) and others.

Did you try using Help > Restart with Add-ons Disabled?

Is your calendar local or are the data stored with a service provider like Google Calendar so as to be available on other devices? If so, you could create a new profile. I haven't resorted to that yet because the Help > Restart workaround works for me at the moment.

It is a local Calendar. I do not want to loose all my calendar history, but was able to download my calendar history as a reference if needed. Yes I did the restart with add-ons disabled and cannot find a solution. Tony

When I do get the calendar back with old history, I cannot add any new event. Then tried everything all over and loose calendar with history.

Looks like you may have to create a new profile then. Before you do anything else, make sure you have a full back-up copy of your current TB profile (usually on W10 this is stored in C:\Users\<your account>\AppData\Roaming\Thunderbird\Profiles).

I'm going to try to create a new profile in a couple of days, I'll post back with the results.

Very frustrating and considering going to a different mail program although I have been with Thunderbird for years.

Frustrating indeed. Same here, I've been using TB for years.

I tried creating a new profile, configured an IMAP account + Google calendar + local calendar. All works perfectly, as expected. If I were to go that way, the problem above all, would be transferring local e-mail folders (I have many) from one profile to the other, and getting the local calendar data from the old profile.

Were you able to export your Home (local) calendar as an .ics? If you don't have much in the way of local e-mail folders (in which case you probably use IMAP) then creating a new profile might be your best option at the moment. You'd just need to re-import the .ics and you'd be away.

If you want to try that, read up on profiles and Profile Manager.

That didn't work either by changing profile. UGH.

Has anyone had success is getting their calendar to work after TB update? I can get the calendar to appear, but it does not show any history nor will it allow me to add a new event. Tried the suggestions of going to editor etc and it does not work.

despite suggestion in this forum, most people are having no issues with the calendar at all.

BTW I have no idea what editor config your talking about. Nor do I even know if your calendar is not read only.

What I do know in Thunderbird 68 is the last version of Thunderbird that will have a calendar addon.  It will be integrated in the next release.

The first think I do with calendar issues is look at the calendar name on the left of the calendar tab under the little month calendar. It generally places an icon beside a calendar that has issues and a tool tip that offers some information.

The second thing it I open the error console (ctrl+Shift+J) and clear it. Then try and edit the calendar and see what error that creates if any.

At this point I have no feeling about your issues as you start the thread indicating it is broken completely and later you talk about history. Which is it?

Each time I open TB, the calendar does not appear which it always did in the past. I used the Mozilla tools, options, advanced, config editor as they suggest online. I follow all the steps and finally the calendar appears but without history nor does New Events work. Doing this a couple of times and finally calendar comes up with history, but new events will not work. When I close TB and open it a day later, same old problem with no calendar etc.

Hi, Just solved the pb I had with Lightning. As yours may be related, have a look. https://support.mozilla.org/en-US/questions/1273975