Warning: The name 'Foo' does not exist in the current context

ASP.NET 3.5 C# VS2008 I have a webusercontrol that inherits from MyWebControl.ascx class. MyWebControl inherits from System.Web.UI.UserControl
MyControl class has method Foo();
When I open MyWebControl in VS it gives me the warning: The name 'Foo' does not exist in the current context
How to structure the project in this case?
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