Could not load type from assembly error

Question

I have written the following simple test in trying to learn Castle Windsor's Fluent Interface:

using NUnit.Framework;
using Castle.Windsor;
using System.Collections;
using Castle.MicroKernel.Registration;

namespace WindsorSample {
    public class MyComponent : IMyComponent {
        public MyComponent(int start_at) {
            this.Value = start_at;
        }
        public int Value { get; private set; }
    } 
    public interface IMyComponent {
        int Value { get; }
    }

    [TestFixture]
    public class ConcreteImplFixture {
        [Test]
        public void ResolvingConcreteImplShouldInitialiseValue() {
            IWindsorContainer container = new WindsorContainer();
            container.Register(Component.For<IMyComponent>().ImplementedBy<MyComponent>().Parameters(Parameter.ForKey("start_at").Eq("1")));
            IMyComponent resolvedComp = container.Resolve<IMyComponent>();
            Assert.AreEqual(resolvedComp.Value, 1); 
        }
    }
}

When I execute the test through TestDriven.NET I get the following error:

System.TypeLoadException : Could not load type 'Castle.MicroKernel.Registration.IRegistration' from assembly 'Castle.MicroKernel, Version=1.0.3.0, Culture=neutral, PublicKeyToken=407dd0808d44fbdc'.
at WindsorSample.ConcreteImplFixture.ResolvingConcreteImplShouldInitialiseValue()

When I execute the test through the NUnit GUI I get:

WindsorSample.ConcreteImplFixture.ResolvingConcreteImplShouldInitialiseValue:
System.IO.FileNotFoundException : Could not load file or assembly 'Castle.Windsor, Version=1.0.3.0, Culture=neutral, PublicKeyToken=407dd0808d44fbdc' or one of its dependencies. The system cannot find the file specified.

If I open the Assembly that I am referencing in Reflector I can see its information is:

Castle.MicroKernel, Version=1.0.3.0, Culture=neutral, PublicKeyToken=407dd0808d44fbdc

and that it definitely contains Castle.MicroKernel.Registration.IRegistration

What could be going on?

I should mention that the binaries are taken from the latest build of Castle though I have never worked with nant so I didn't bother re-compiling from source and just took the files in the bin directory. I should also point out that my project compiles with no problem.

Answer 1

If you have one project referencing another project (such as a 'Windows Application' type referencing a 'Class Library') and both have the same Assembly name, you'll get this error. You can either strongly name the referenced project or (even better) rename the assembly of the referencing project (under the 'Application' tab of project properties in VS).