The number of arguments is not valid for the operator '', '':''. The number of children is not valid for the element '', '':''. The query is invalid. The operand type is not valid for the operator '', '':''. MDXWriter Error. The MDQuery operator '' is unknown. MDXWriter error. The input is not an MDQuery element. MDXWriter error. The supplied cube name is empty or not valid. MDXWriter error. Encountered an invalid element '', '':''. The MDQuerySpec is invalid. The 'otherwise' element in the IF-Then-Else expression is either missing or not valid, '':''. The query is not valid. The dateTime value '' is not valid. '':''