[in, out] BOOL – When set to FALSE, TerraExplorer errors that occur during a COM method call are not displayed to the user. If this property is set to TRUE and an error occurs during a COM method call, TerraExplorer displays a message box for the user describing the nature of that error. In both cases, the caller, using the standard IErrorInfo interface, can retrieve the error description after the COM method call is returned. The default value for this property is TRUE.