Rebar   |  
 The reason for calculation failure. If the calculation fails, this message will be shown in an error, or warning if we are editing the constraints. 
 Namespace: Autodesk.Revit.DB.Structure
Assembly: RevitAPI (in RevitAPI.dll) Version: 25.0.0.0 (25.0.0.0)
| Exception | Condition | 
|---|---|
| ArgumentException | When setting this property: errorMessage is an empty string. | 
| ArgumentNullException | When setting this property: A non-optional argument was null |