I have tried this already, but will try again. However, when I deleted Google Calendar Provider just now and re-started Tbird, I received an (unusual) request to log in to my Google account ; after logging in, I received an error message from Google

" Oops! Your browser seems to have cookies disabled. Make sure cookies are enabled or try opening a new browser window".

This was the first error message I received after the Calendar stopped syncing : cookies were then - and are still now - enabled, but Google Calendar doesn't seem to recognize this.

I uninstalled Provider for Google Calendar and manually re-started Tbird (it did not re-start automatically as it should have).

On re-start, got the same request (unusual) request to log in to Google, then the same error message regarding enabling cookies (which are still enabled).

Are you certain your calendar isn't set-up as CalDAV? Can you provide a screenshot of your cookie settings in Thunderbid?

Hi

Here is a s/s showing that cookies are enabled in Tbird

Hi here are cookie settings

I did check that CalDav was not used for the set-up, but would you pls remind me how to verifiy this?

You right-click the calendar in the left pane of Lightning - Properties. What's set under 'Location'?

Can you confirm you still see the calendar, even after deleting the Provider add-on?

Location is set to : googleapi://name@name.com/?calendar=name%40name.com&tasks=%40default

I deleted Provider add-on and re-started Tbird ; Calendar is still there.

Ok, what happens when you re-install the Provider add-on? Note, version 1.0.1 is available on AMO now.

I have 1.0.1 and it still doesn't work

When I try to re-install Provider 1.0.1, I get an error message :

"There was an error downloading Provider for Google Calendar" and a "try again" link ; made several attempts (closing/re-starting Tbird each time), but can't download this.

so maybe it's a provider problem and google has changed something and it's not been updated in the provider plugin ??

Downloading Provider from AMO works fine here. https://addons.mozilla.org/en-US/thunderbird/addon/provider-for-google-calendar/ So you may have other problems not related to Thunderbird.

If things don't work out for you using Provider, you can still try to set-up your Google Calendar as CalDAV. https://blog.mozilla.org/calendar/2013/09/google-is-changing-the-location-url-of-their-caldav-calendars/

I was able to install Provider again using the link above ; I don't know why the install does not work from within Tbird.

However, when Tbird restarts, I get the same (unusual) request to sign into Google and same error message as before telling me that my browser has cookies disabled...but it doesn't :(

I'll try CalDAV...

I re-installed google provider from file and it has not solved the matter.

Hi again, Just to be sure that I understand : I need to download Thunderbird 24 and install Lightning 2.6 to set up CalDav, in other words, downgrade to an earlier version of both apps?

... downgrade to an earlier version of both apps?

God, no. Just follow the installation instructions and keep the latest versions of both, Thunderbird, and Lightning.

OK I installed a new CalDav calendar using latest versions of Thunderbird and Lightning but when I open Tbird, Google STILL asks me to sign in (why?) and STILL rejects the log in with a request to enable cookies, which are STILL enabled.

I recently changed my Google password and when searching around, found that in Tools/Options/Saved Passwords, Tbird had two different passwords for the Google calendar (old and new).

I deleted the old password, closed Tbird and re-opened, but still not possible to enable either of the calendars...

Arggh.

Google STILL asks me to sign in (why?)

Because this is a new way of signing in, and Thunderbird didn't remember the password for the CalDAV method (yet).

STILL rejects the log in with a request to enable cookies

Do you have any exceptions for cookies? Also try to clear cookies.

Tbird had two different passwords for the Google calendar

The 'old' one probably was the one for the 'Provider' method.