The PreferredCalendarGroupExtent indicates the extent that each CalendarGroup should be when arranged. If the available space is less than the preferred extent, the available space will be used. Also, if AllowCalendarGroupResizing is enabled, this property will be updated as the user drags the resizer bar at the right edge of the group.
Target Platforms: Windows 10, Windows 8.1, Windows 8, Windows 7, Windows Server 2012, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2