c# Cant get AssemblyResolve working in combination with CreateInstanceAndUnwrap

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C#3.0

C#

Hi
I’ve been struggling for the past couple of days with at problem with AsssemblyResolve.
What I want to achieve is a setup for a service that can update and cache assemblies from a URL, and be able to Create and UnLoad an AppDomain without restarting the service.
But my problem is much simpler, and I have created a minimized sample, which illustrate my problem.
1: a console exe with a Loader

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Reflection;
using System.IO;

namespace TestAppDoms
{
    public static class Loader
    {
        static void Main()
        {
            AppDomain.CurrentDomain.AssemblyResolve += FindAssem;
            Program.GO();
        }

        public static Assembly FindAssem(object sender, ResolveEventArgs args)
        {
            string shortName = new AssemblyName(args.Name).Name;

            using (FileStream fs = File.OpenRead(Path.Combine(@"C:\TestAssem\", shortName + ".dll")))
            {
                byte[] assemBin = new byte[fs.Length];
                fs.Read(assemBin, 0, Convert.ToInt32(fs.Length));
                Assembly Assem = Assembly.Load(assemBin);

                return Assem;
            }
        }
    }

    public class Program
    {
        public static void GO()
        {
            brokerCtrl brkCtrl = new brokerCtrl();
            brkCtrl.Run();
            Console.ReadLine();
        }
    }
}

2: a dll (symbolizing the a cashed assembly)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Reflection;
using System.IO;

namespace TestAppDoms
{
    public class brokerCtrl
    {
        public void Run()
        {
            Console.WriteLine("Hello From Ctrl.dll " + AppDomain.CurrentDomain.FriendlyName);
            
            AppDomainSetup setup = new AppDomainSetup();
            setup.ApplicationBase = AppDomain.CurrentDomain.BaseDirectory;
            setup.ConfigurationFile = AppDomain.CurrentDomain.SetupInformation.ConfigurationFile;
            AppDomain brokerDom = AppDomain.CreateDomain("b2bBroker", AppDomain.CurrentDomain.Evidence, setup);
            brokerDom.AssemblyResolve += new ResolveEventHandler(brokerDom_AssemblyResolve);
 
            BrokerWrapper brokerProxy = (BrokerWrapper)brokerDom.CreateInstanceAndUnwrap(typeof(BrokerWrapper).Assembly.FullName, typeof(BrokerWrapper).FullName);
            brokerProxy.StartBroker();
            AppDomain.Unload(brokerDom);
            brokerProxy = null;
            
        }

        public static Assembly brokerDom_AssemblyResolve(object sender, ResolveEventArgs args)
        {
            string shortName = new AssemblyName(args.Name).Name;
            Console.WriteLine("Hello from brokerDom_AssemblyResolve");

            using (FileStream fs = File.OpenRead(Path.Combine(@"C:\TestAssem\", shortName + ".dll")))
            {
                byte[] assemBin = new byte[fs.Length];
                fs.Read(assemBin, 0, Convert.ToInt32(fs.Length));
                Assembly Assem = Assembly.Load(assemBin);
                return Assem;
            }
        }
    }

    public class BrokerWrapper : MarshalByRefObject
    {
        public override object InitializeLifetimeService()
        {
            return null;
        }
        public void StartBroker()
        {
            Console.WriteLine("Hello From " + AppDomain.CurrentDomain.FriendlyName);
        }

    }
}

When both TestAppDoms.exe and brokerCtrl.dll are placed in the same directory (and the CLR can locate the dll in the probing path) everything works like a charm.
But when I move the dll away from the exe (to the C:\TestAssem\ ) The brokerDom.AssemblyResolve += new ResolveEventHandler(brokerDom_AssemblyResolve) never fires - as expected.

Obviously I overlook something.

Can anybody help me solve my problem?

Best, Robert