I'm not aware of a limit - but I imagine that too many values are going to cause a problem.  Off the top of my head seems like in Information Map Studio suggest you limits the choices to a 100 values.  This may be more of a design issue (if you don't mind me saying).  As an end user, I would have a hard time picking from a list of 200000 choices.  You might want to consider adding some extra grouping and using a cascaded prompt.  I talk about cascading prompts in this blog post, if you need some extra help: Stored Process: Need to prompt based on the first prompt value? I notice that the error indicates it didn't like the LIBREF - so I'd be curious if the lookup table location had the necessary permissions. Hope this helps Tricia ... View more