Right Clicking on the result set, and selecting:
Quick Export | File | Excel File...
then the error shows up:
Exception in WriteRows
Object reference not set to an instance of an object
Writing rows Finalize
Object Table Result Set finished with error: Object reference not set to an instance of an object.
at Quest.Toad.ImportExport.Writers.WriterBase.WriteRows(FastTable fastTable)
at Quest.Toad.ImportExport.ExportObjectData.StartTableWrite(Object context)
at Quest.Toad.ImportExport.ExportObjectData.Begin(LogEventHandler logEventHandler, Dictionary`2 connections, Object context)
Export Finished