gennet40 -o SRC:NetWrappers.dbl MYBIN:MyAssembly.dll

<?xml version='1.0'?>
<assemblies>
    <assembly Name="MYBIN:MyAssembly.dll">
        <class Name = "MyBarChart"/>
        <class Name = "MyLineChart"/>
    </assembly>
</assemblies>

Hi Steve,

Please clone the following Git Repository https://github.com/aolszowka/SynergySamples/tree/SRC-0870d000000bppFAAQ

Build this (either in x64 or x86) and attempt to execute, this will reproduce the issue.

The secret sauce is attempting to have WPF attempt to load a dependent assembly (in this case System.Windows.Interactivity) which causes this to fail with the following FUSLOGVW Error:
 

*** Assembly Binder Log Entry  (6/8/2020 @ 3:02:02 PM) ***

The operation failed.
Bind result: hr = 0x80070002. The system cannot find the file specified.

Assembly manager loaded from:  C:\Windows\Microsoft.NET\Framework\v4.0.30319\clr.dll
Running under executable  C:\Program Files (x86)\Synergex\SynergyDE\dbl\bin\dbr.exe
--- A detailed error log follows. 

=== Pre-bind state information ===
LOG: DisplayName = System.Windows.Interactivity, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35
 (Fully-specified)
LOG: Appbase = file:///C:/Program Files (x86)/Synergex/SynergyDE/dbl/bin/
LOG: Initial PrivatePath = NULL
LOG: Dynamic Base = NULL
LOG: Cache Base = NULL
LOG: AppName = dbr.exe
Calling assembly : PresentationFramework, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35.
===
LOG: This bind starts in default load context.
LOG: No application configuration file found.
LOG: Using host configuration file: 
LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework\v4.0.30319\config\machine.config.
LOG: Post-policy reference: System.Windows.Interactivity, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35
LOG: GAC Lookup was unsuccessful.
LOG: Attempting download of new URL file:///C:/Program Files (x86)/Synergex/SynergyDE/dbl/bin/System.Windows.Interactivity.DLL.
LOG: Attempting download of new URL file:///C:/Program Files (x86)/Synergex/SynergyDE/dbl/bin/System.Windows.Interactivity/System.Windows.Interactivity.DLL.
LOG: Attempting download of new URL file:///C:/Program Files (x86)/Synergex/SynergyDE/dbl/bin/System.Windows.Interactivity.EXE.
LOG: Attempting download of new URL file:///C:/Program Files (x86)/Synergex/SynergyDE/dbl/bin/System.Windows.Interactivity/System.Windows.Interactivity.EXE.
LOG: All probing URLs attempted and failed.

The lines in question are in UserControl1.xaml 11-12: https://github.com/aolszowka/SynergySamples/blob/de73173127bce536a1e8778c996e7c97a0095408/DotnetAssembly/CSharpInterop/UserControl1.xaml#L11-L12

In your defense attempting to load several other binaries without putting WPF into the mix appears to work as you describe, but CU's setup, as per usual, is always more exotic. I do not know enough about the underlying implementation of WPF to know how they are attempting to load the assembly in question, but my suspicion is when the Traditional Runtime (dbr.exe) hosts the CLR, it does not repoint the ApplicationBase in all scenarios.

Your PR strips the WPF Component which shows the issue in question, as noted above:

attempting to load several other binaries without putting WPF into the mix appears to work as you describe, but CU's setup, as per usual, is always more exotic. I do not know enough about the underlying implementation of WPF to know how they are attempting to load the assembly in question, but my suspicion is when the Traditional Runtime (dbr.exe) hosts the CLR, it does not repoint the ApplicationBase in all scenarios.

What you are showing here is the simple case which does work.

Lets focus on the load failure with WPF first, then loop back around for questions on the above for the simple scenario.

private static System.Reflection.Assembly CurrentDomain_AssemblyResolve(object sender, ResolveEventArgs args)
{
    try
    {
        var assemblyName = args.Name;
        if (!args.Name.EndsWith(".dll"))
        {
            var postName = args.Name.IndexOf(",");
            if (postName > -1)
                assemblyName = args.Name.Substring(0, postName);

            assemblyName += ".dll";
        }
        else
            assemblyName = System.IO.Path.GetFileName(assemblyName);

        var loadFrom = Environment.GetEnvironmentVariable("EXEDIR");
        var filePath = System.IO.Path.Combine(loadFrom, assemblyName);
        if(File.Exists(filePath))
            return System.Reflection.Assembly.LoadFrom(filePath);
    }
    catch
    { }
    return null;
}

AppDomain.CurrentDomain.AssemblyResolve += CurrentDomain_AssemblyResolve;