When I run this query..

SELECT
{ Except(Nonempty([Dim Product].[Product Name].[Product Name].ALLMEMBERS),([Dim Product].[Product Name].[Product Name].&[Unknown]))}
ON COLUMNS,
HIERARCHIZE( { [Dim Date].[Year].&[2013], [Dim Date].[Year].&[2014], [Dim Date].[Year].&[2015] } )
ON ROWS
FROM [Quality Monitor Cube]
CELL PROPERTIES VALUE, FORMATTED_VALUE, CELL_ORDINAL, FONT_FLAGS, FORE_COLOR, BACK_COLOR

Why does the "Unknown" value still show up?

The NEWBIE