User Agent: Mozilla/5.0 (X11; Linux i686; rv:15.0) Gecko/20100101 Firefox/15.0 Build ID: 2012082500 Steps to reproduce: Created an event and added other persons by mail address - as I did this always. Actual results: No mails are sent to the attendees of the event. This works if the calendar is on my local harddisk. But if it is a CalDAV-based calender no mails are sent. When looking at the error console I get at the same time when I save the event with attendees the following error: Zeitstempel: 25.09.2012 09:01:45 Fehler: [Exception... "'TypeError: aItem.calendar.canNotify is not a function' when calling method: [calIOperationListener::onOperationComplete]" nsresult: "0x8057001c (NS_ERROR_XPC_JS_THREW_JS_OBJECT)" location: "JS frame :: resource://calendar/modules/calProviderUtils.jsm :: cPB_notifyOperationComplete :: line 650" data: no] Expected results: A mail should be sent by Lightning/Calendar.

Please search for existing bug reports before filing a new one. This seems like a duplicate of Bug 788004. Have you enabled offline cache for the calendar?

Hi Stefan, I looked for duplicates and saw the other bug. But as the affected Lightning-version is much higher and I can definietly say it comes only together with CalDAV, I opened a new one. Yes ... Offline cache is activated