ASP file not being able to to find a class that is in the same namespace.

I have an ASP file and a Customer class both in the same namespace. When I compile I receive the error: The type or namespace name 'Customer' could not be found (are you missing a using directive or an assembly reference?). I have checked and the asp page
Inherits="PopupApplication.InitDialog"

And the Customer was created in that namespace and has that namespace in the class file. Can anyone help?

Thanks,

Steve 

 
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