Changes to groups are allowed only in group edit mode. Use the Edit Group command to change to all instances of a group type.
You may use the "Ungroup" option to proceed with this change by ungrouping the changed group instances.
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 25.3.0.0 (25.3.0.0)
Syntax
C#
public static FailureDefinitionId AtomViolationWhenMultiPlacedInstances { get; }