'Declaration Public Property AllowTimeZoneNeutral As Nullable(Of Boolean)
public Nullable<bool> AllowTimeZoneNeutral {get; set;}
Note that this property doesn't prevent display of time-zone neutral activities. It simply disallows the user from creating time-zone neutral activities (appointments, tasks etc...) through the UI.
A time-zone neutral activity is an activity that occurs at the same numerical time value across all time zones. That is, let's say a time-zone neutral activity starts at 9:00 AM. It starts at 9:00 AM local time in every time-zone. Holidays are a good example of time-zone neutral activities where they start at, let's say 12:00 AM, regardless of the time-zone.
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