Problem:

Solution:

The behavior described herein applies to Groupcal 3.30 and newer.

Although iCal and Exchange do not support the same collection of alarm capabilities, Groupcal preserves alarms when possible (i.e., there's no need to be alarmed because you should still be alarmed!).

Exchange only supports a reminder/display/message (Outlook name/RFC name/iCal name - respectively) that occurs before the event in question.

The Apple schema specification for iCal does not support "Run script" or "Open file" alarms. Therefore, "Run script" and "Open file" alarms are ignored when syncing to Exchange and can be lost if the event is changed in Exchange or restored from Exchange.

All other iCal alarms are converted to a reminder alarm if the alarm occurs before the event. If an alarm occurs after the event, the alarm will be ignored when sync'd into Exchange.

The alarm will, however, be stored into Exchange in a way that it can be properly restored to iCal if the iCal calendar is deleted then re-created and its restored by syncing from Exchange (as a long as the event was not modified in Exchange since that would cause Exchange to remove the extra information Groupcal stores in the event to be able to restore the alarms).

These behaviors have multiple implications. The following are some examples:

E.G., (in iCal) create an event with an alarm, sync to Exchange, delete the iCal calendar, recreate the iCal calendar and sync to restore the iCal's calendar contents from Exchange. The alarms (except "Run script" or "Open file" alarms) will be restored properly.

E.G., (in iCal) create an event with an alarm before the event, sync to Exchange, modify that event in exchange, sync back to iCal. The event alarm (that Exchange was showing) will now have been converted to a reminder/message alarm in iCal.

E.G., (in iCal) create an event with alarm after the event, sync to Exchange, modify that event in Exchange (note alarm is gone since Exchange doesn't support alarms after events), sync back to iCal. The event will now have no alarm in iCal.

The "Reminder Sound" property is not provided to Groupcal (because Exchange doesn't add it to the VCalendar).

The to-do/task interface to Exchange is different than for events and does not provide a way to add custom properties. The result is that task alarms have the same behavior as event alarms except that they cannot be restored from Exchange (i.e., if the iCal task/alarm is sync'd to Exchange, the iCal calendar is deleted then re-created and the calendar contents are restored by syncing from Exchange, the task alarms will be lost).