Controlled Application Register Failures Processor Method

Parameters

processor IFailuresProcessor

Instance of Failures Processor to be used by the Revit Application.

Exception	Condition
ArgumentNullException	A non-optional argument was NULL

If there is previously registered Failures Processor, it gets discarded. If you opt to register a FailuresProcessor for Revit, your processor will become the default error handler for all Revit errors for the session. The standard Revit error dialog will not appear. If you want to handle only specific failures but not all types of failures in your application, subscribe to the FailuresProcessing event instead, or use FailuresPreprocessor interface for the specific transaction.

Reference