Rated 5 out of 5 stars

At fist, I encountered the same problems described in the previous comment titled "Broken".
Thunderbird froze after adding a Google Calender.
After killing the Thunderbird process and restarting (in normal mode), it seemed to work fine.
However, Thundebird froze again when I added my first test event to the calendar.
After killing the Thunderbird process once or twice, it finally seems to work fine.

I am not sure why I encountered these issues at first (maybe this is the "issues with Google's API access rules" mentioned in the add-on's description?), but they appear to be gone now: I can read and write events to my Google calendar as expected.

Haven't tried tasks which are not yet supported according to the description.

My system specs:
* Windows Vista, SP 1
* Thunderbird 24.0
* Lightning 2.6
* Provider for Google Calendar 0.25

This review is for a previous version of the add-on (0.25). 

Rated 1 out of 5 stars

It's always been a bit temperamental in the past, but the latest version simply seems to throw [Exception... "[xpconnect wrapped nsIURI]" nsresult: "0x804b000a (NS_ERROR_MALFORMED_URI)"errors now when trying to connect to Google Calendar via Lightning. It also seems to hang on startup, to the point where I had to start Thunderbird with the "-p" option and delete my working profile entirely to start afresh. Shame...

This review is for a previous version of the add-on (0.25). 

Rated 2 out of 5 stars

it is very limited, you can not choose an email for this calendar type to use if a calendar invite will be received via email, and it is not possible to add this to calendar

This review is for a previous version of the add-on (0.25). 

Rated 2 out of 5 stars

TB 24, provider 0.25 with Lightning 2.6: TBird always freezes unless I deactivate Provider for Google Agenda.

With previous versions of Provider and TB and for years, always had major system slow down while Provider was syncing, even making other apps fail, no matter if it was on WIndows or Ubuntu Linux (yes I carry a big bunch of events with it, but a reliable add-ons shouldn't worry about it).

May be good stuff for amateur with almost nothing in terms of data volumes but absolutely a bunch of trouble for serious production environment.

Until a version 1.x is released am looking for a reliable way to sync Lightning with Google.

This review is for a previous version of the add-on (0.25). 

Rated 5 out of 5 stars

Since 2 days (09/06/2013/ the plugin cant connect to my gmail calendar, yellow icon with a warning message something like: The calendar is actually not available.. but thats not true, i can access to it from my Android device with no problems.. any problem?

Note: I need to delete the old one, install the new beta version and delete my actual calendar and create a new one, now its working again

This review is for a previous version of the add-on (0.18). 

Rated 1 out of 5 stars

This made Thunderbird freeze and then keep freezing every time I started it up so . In the end I had no alternative but to delete my ~/.thunderbird folder and start again, including re-syncing several hours worth of IMAP data.

This review is for a previous version of the add-on (0.18). 

Rated 1 out of 5 stars

Installed this to get better access to google calendar. Running T-bird 17.0.8 Lightning 1.9.1 and all it does is hang, make thunderbird completely unresponsive, and crash.

This review is for a previous version of the add-on (0.18). 

Rated 2 out of 5 stars

I really like this add-on and was fine until something between Thunderbird/Lightning and Google Calendar decided to take control over events that were originally created from my Outlook at work. Suddenly it (one or other) is sending and re-sending meeting invites updates and cancellations as if I was the organiser!!! This has cause huge confusion and upset amongst work colleagues and I've had to disable the Thunderbird calendar.
I doubt that it is actually the add-on that is causing the problem but something between T'bird, Google an Outlook events. Either way cant find a fix online and so have had to revert to using the default Mac calendar which ain;t brilliant but does not have this problem.

This review is for a previous version of the add-on (0.18). 

Rated 3 out of 5 stars

I've been using this addon for about a day (will update if my experiences change) and I am reasonably pleased. Adding my calendar was simple enough, and syncing seems to occur smoothly.I manged to copy the events from my default Home calendar to Google calendar through import/export functions. One day's event times needed to be fixed, but overall the copy was effective.One problem I do have is the lack of task support. I use tasks constantly, and would love to have mobile access via Google tasks. Also, to use them locally now, I had to create a new "Tasks" calendar for tasks only. This requires me to be very careful when adding new events, so as to make sure they go to the Google calendar and are later synced. Hopefully, task support is coming soon.All in all, a good addon though.

EDIT: Just noticed that I can't write to the Google calendar when in offline mode. It gives me errors. I lowered my rating because of this. It would be far more convenient if events would queue to sync once connectivity was reestablished.

This review is for a previous version of the add-on (0.18). 

Rated 4 out of 5 stars

This add-on goes very fine with my TB 17.0.5 and Lightning 1.9, both in my office and at home. But not off-line ! . I found this last week during a conference when I launched TB without internet connection, and TB hanged badly, consuming a lot of CPU. After many trials I finally found a (the?) solution: just disabling "Provider for Google Calendar". It would be great to have this add-on working also for off-line use.

This review is for a previous version of the add-on (0.18). 

Rated 2 out of 5 stars

when started 5 days ago it was working.
Now it is empty, and shows exclamation mark in yellow triangle, it says "calendar google is not accessible this time" .

what to do?

This review is for a previous version of the add-on (0.18). 

Rated 1 out of 5 stars

It used to be the only way to read/write on google calendars. It stopped working with new versions of Lightning (>1.9.1). It cannot log-in to my google (gmail) calendar account anymore. It keeps asking me the password as if it is not recognized. Useless now :-((

This review is for a previous version of the add-on (0.18). 

Rated 3 out of 5 stars

This was excellent for sync'ing calendars with my Android but has stopped working properly a couple of weeks ago. I get a frequent dialog (as per sync frequency, i guess) that says "An error occurred when writing to the calendar Work!" and "Error code: MODIFICATION_FAILED". I once solved the problem by deleting the calendar and re-defining it. Now the problem ahs recurred. I am unable to find a reason through Google - no record of recent changes that could have caused this.

This review is for a previous version of the add-on (0.18). 

Rated 1 out of 5 stars

Chews up an enormous amounts of memory and hangs system.

This review is for a previous version of the add-on (0.18).  This user has a previous review of this add-on.

Rated 1 out of 5 stars

Memory hang; continuous drain until freezes. Please fix. This add-on was great.

This review is for a previous version of the add-on (0.18). 

Rated 5 out of 5 stars

does exactly what it says

This review is for a previous version of the add-on (0.18). 

Rated 4 out of 5 stars

This add-on provides a wonderful service to the Thunderbird application, making integration with the Google Calendar seamless. Make a change on your desktop and it automatically updates Google Calendar, and vis-a-versa. Everything syncs beautifully.

Only problem is that when attempting to move the Calendar tab to a new window, Thunderbird hangs and the only solution is to force close the application and restart.

It's not a show-stopper, but would make life even easier if the Calendar could be opened in a separate window from the email client.

Stopping the Provider for Google Calendar add-on resolves the problem, but at the cost of eliminating Google Cal integration.

This review is for a previous version of the add-on (0.18). 

Rated 5 out of 5 stars

Exceptional ext/add-on works and has made my life easier as far as calendars go. Thanks for all the hard work in producing this add-on. Would like to donate $$$ but unless you are willing to take Jamaican dollars then.....sorry. If however you are ever in Jamaica please link me and I will treat you to the best Jerk Chicken and Pork in the world. Your add-on is sincerely appreciated.

This review is for a previous version of the add-on (0.18).  This user has a previous review of this add-on.

Rated 5 out of 5 stars

This add-on work well with multiple Google accounts while the CalDAV support does not. Additionally, Google is
dropping support for CalDAV, but this addon uses not rely on CalDAV. http://googleblog.blogspot.com.au/2013/03/a-second-spring-of-cleaning.html

This review is for a previous version of the add-on (0.18). 

Rated 5 out of 5 stars

Hi,

I've used Lightning for many months (I can't recall when I migrated to Tbird ... :) and I'd occasionally encounter issues where I couldn't dismiss a Google Calendar reminder.

Last week it got so bad that I had 12+ reminders. I could have worked-around it by suppressing passed-due reminders but instead, I applied a work-around that was recommended: Lightning + Provider (for the actual connection to Google Calendar). Problem resolved!

Thank you!

This review is for a previous version of the add-on (0.18).