Reference Paths Page, Project Designer (C#)
Use the Reference Paths page to specify the folder path for assembly references used by the project.
When the project system finds an assembly reference, it is resolved by looking in the following locations, in order:
The project directory. These files appear in Solution Explorer when Show All Files is not in effect.
Directories specified in this dialog box.
Directories displaying files in the Add Reference Dialog Box.
The project's obj directory. (Any assemblies created as a result of adding a COM reference to your project are added to the project's obj directory.)
For more information, see How to: Set the Reference Path (C#)