CalDAV Clients/Mozilla Calendar

Currently Supported Version
The recommended version of Sunbird / Lightning to use at present is the latest release which should work well with any recent release of DAViCal. See the Mozilla calendar blog and home page for the latest information.

In general, the currently released Lightning should work with the currently released DAViCal. Mozilla Calendar is a core target and any bugs should be stomped aggressively.

Free/Busy Support
This should work, but you need to identify participants in meetings by their e-mail addresses, so make sure your users have their e-mail addresses entered into DAViCal correctly.

Enabling Debugging
To enable debug logging in Mozilla Calendar, you need to set the following preferences to 'true' in the Preferences -> Advanced -> General -> Config Editor. To find these entries, use "calendar.debug.log*" for filtering the configuration. If the entries should not exist, simply create them. No, it's not supposed to be easy, I guess.

The debug output can be seen either via Extras -> Error console or on stdout/stderr if you have started Mozilla Calendar from the command line.

Troubleshooting
The Mozilla Calendar is quite slow when it comes to large calendars. If a calendar is marked as unavailable with an exclamation mark, but other clients can happily access the calendar or other calendars work without problems, look in the error console. If there is a READ_FAILED and a status code 200 for the calendar, consider increasing the resource limits in php.ini on the server. Look for max_execution_time and memory_limit.