Default reminder not working in Thunderbird Lightning calendar

You may encounter the problem that the default reminder does not work any more if you access the Google calendar through Provider for Google Calendar in Thunderbird Lightning. Whenever you create a event and use the Default Reminder, it does not work. If you edit that event, you will find the reminder option is set to No reminder. However, in Options --> Calendar --> Alarms, Reminders are set to on for events.  Thus it should add a reminder by default. In about:config, you may find similar entries like
calendar.registry.*****-******-******-******-******.settings.defaultReminders
and the value is set to [].

Why the Alarms setting does not work on the Google calendar? This problem occurs because you have NOT set a reminder in Google calendar settings through web interface, and it is inherited to your local computer. To solve the problem, follow the steps below.

1. Log in to Google Calendar web interface (https://www.google.com/calendar);
2. Go to Settings -->Calendars and find out the calendars you would like to add a default reminder.
3. On the right side of the calendar name, click on Edit notifications.
4. In the Event notifications, add a pop-up notification.
5. Quit Thunderbird and restart it.

No actions are taken when double click on an attachment in Thunderbird

This is a known problem and has been discussed in MozillaZine Knowledge Base (http://kb.mozillazine.org/Actions_for_attachment_file_types).

In summary, the following steps should be taken to solve this problem.

1. Make sure Thunderbird is NOT running.

3. Delete mimeTypes.rdf from hte Thunderbird profile folder.

In Windows XP, it is usually at C:\Documents and Settings\\Application Data\Thunderbird\Profiles\; In Vista and Windows 7, it is at C:\Users\\AppData\Roaming\Thunderbird\Profiles\\.

4. Restart Thunderbird. Now if you double click on an attachment, it should ask you which action you want to take.