"Inheritance security rules violated" when using HttpSelfHostServer and IDependencyResolver

Question

I am trying to use HttpSelfHostServer to install ASP.NET MVC 4 WebAPI myself. Everything is fine, I am trying to add a custom dependent converter. (Ultimately this will use StructureMap, but I haven't even reached that point yet). If I try to create an instance of a custom resolver, I get the following exception when starting the server:

TypeLoadException: inheritance security rules violated by type: 'System.Web.Mvc.CompareAttribute. Derived types must either comply with the security of accessibility of the base type or be less accessible.

The code is as follows:

public class CustomDependencyResolver : IDependencyResolver { public object GetService( Type serviceType ) { return null; } public IEnumerable<object> GetServices( Type serviceType ) { return null; } } ... // To trigger the exception, all I need to do is instantiate the custom resolver. var dependencyResolver = new CustomDependencyResolver(); // Exception is thrown when I create the server: var server = new HttpSelfHostServer( _config ); 

Please note that I don’t need to do anything with the converter - this is simp, y is the action of creating an instance, which later causes an error.

Oddly enough, this exception only occurs when debugging (F5) - if I run through Ctrl + F5, everything works fine.

Any thoughts on how to solve this?

Stacktrace:

 mscorlib.dll!System.Reflection.RuntimeAssembly.GetExportedTypes() + 0x27 bytes System.Web.Http.dll!System.Web.Http.Dispatcher.HttpControllerTypeCacheUtil.FilterTypesInAssemblies(System.Web.Http.Dispatcher.IBuildManager buildManager, System.Predicate<System.Type> predicate) + 0x104 bytes System.Web.Http.dll!System.Web.Http.Dispatcher.HttpControllerTypeCacheUtil.GetFilteredTypesFromAssemblies(string cacheName, System.Predicate<System.Type> predicate, System.Web.Http.Dispatcher.IBuildManager buildManager) + 0x76 bytes System.Web.Http.dll!System.Web.Http.Dispatcher.HttpControllerTypeCache.InitializeCache() + 0x58 bytes System.Web.Http.dll!System.Web.Http.Dispatcher.HttpControllerTypeCache.HttpControllerTypeCache(System.Web.Http.HttpConfiguration configuration) + 0x96 bytes System.Web.Http.dll!System.Web.Http.Dispatcher.DefaultHttpControllerFactory.DefaultHttpControllerFactory(System.Web.Http.HttpConfiguration configuration) + 0x96 bytes System.Web.Http.dll!System.Web.Http.Services.DefaultServiceResolver..ctor.AnonymousMethod__0(System.Web.Http.HttpConfiguration config) + 0x30 bytes System.Web.Http.dll!System.Web.Http.Services.DefaultServiceResolver.GetService(System.Type t) + 0x57 bytes System.Web.Http.dll!System.Web.Http.Services.DependencyResolver.GetService(System.Type serviceType) + 0xd3 bytes System.Web.Http.dll!System.Web.Http.DependencyResolverExtensions.GetService<System.Web.Http.Dispatcher.IHttpControllerFactory>(System.Web.Http.Services.DependencyResolver resolver) + 0x6a bytes System.Web.Http.dll!System.Web.Http.DependencyResolverExtensions.GetServiceOrThrow<System.Web.Http.Dispatcher.IHttpControllerFactory>(System.Web.Http.Services.DependencyResolver resolver) + 0x5b bytes System.Web.Http.dll!System.Web.Http.DependencyResolverExtensions.GetHttpControllerFactory(System.Web.Http.Services.DependencyResolver resolver) + 0x25 bytes System.Web.Http.dll!System.Web.Http.Dispatcher.HttpControllerDispatcher.HttpControllerDispatcher(System.Web.Http.HttpConfiguration configuration) + 0x77 bytes System.Web.Http.SelfHost.dll!System.Web.Http.SelfHost.HttpSelfHostServer.HttpSelfHostServer(System.Web.Http.SelfHost.HttpSelfHostConfiguration configuration) + 0x62 bytes WebApi.Host.dll!My.WebApi.Host.Server.Listen() Line 33 + 0x1b bytes C# Services.TrialBalance.TestHarness.exe!Digita.AccountsPro.Services.TrialBalance.TestHarness.Program.Main() Line 21 + 0xa bytes C# [Native to Managed Transition] [Managed to Native Transition] mscorlib.dll!System.AppDomain.ExecuteAssembly(string assemblyFile, System.Security.Policy.Evidence assemblySecurity, string[] args) + 0x6d bytes Microsoft.VisualStudio.HostingProcess.Utilities.dll!Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly() + 0x2a bytes mscorlib.dll!System.Threading.ThreadHelper.ThreadStart_Context(object state) + 0x63 bytes mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state, bool ignoreSyncCtx) + 0xb0 bytes mscorlib.dll!System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext executionContext, System.Threading.ContextCallback callback, object state) + 0x2c bytes mscorlib.dll!System.Threading.ThreadHelper.ThreadStart() + 0x44 bytes [Native to Managed Transition] 

Answer 1

Finally found the answer; therefore, answering my own question.

Two IDependencyResolver : one in System.Web.Http.Services and one in System.Web.Mvc .

Both compile and run without debugging.

System.Web.Http.Services.IDependencyResolver is correct .

System.Web.Mvc.IDependencyResolver seems to be causing problems.