C# .net and SWx2007

When I try and build a C# project in VS2005 I get the following build error:

The type or namespace name 'OuterDispProxy' does not exist in the namespace 'SolidWorks' (are you missing an assembly reference?). I can't find a reference to the SolidWorks.OuterDispProxy anywhere. any ideas?

SolidworksApi macros