Yes - you might be right about the solution explorer. Unfortunately, the machine I am on right now doesn't have 2005. However, there still has to be a place where your references in your project can be viewed, is there not? Wherever that is it would be helpful to determine if you are specifically referencing a the System.Data.SqlClient.dll. Unless I am way off on this, your project should NOT be referencing this dll. This could be causing an ambiguity or other problem that manifests itself in the behavior you are experiencing.