The elements you have selected for grouping contain dimensions or tags whose references are not all included in the selection being
grouped and are not all included in a common model group.
As a result, some of the selected elements have not been included in the new group.
Namespace: Autodesk.Revit.DB
Assembly: RevitAPI (in RevitAPI.dll) Version: 26.1.0.0 (26.1.0.34)
Syntax
C#
public static FailureDefinitionId ReferencesOutsideGroupAreNotAllowed { get; }