Could not load type 'System.IdentityModel.Tokens.JwtSecurityToken'

I have two libraries. One consumes the other, and the consuming library is itself used by the web application. The web app returns the error below, whereas the code instantiating the type (JWT signature dope check) runs successfully in unit tests by both libraries. libraries, application is target .NET 4.5.2 I have verified that the .csproj file for the web application has a valid link

<Reference Include="System.IdentityModel.Tokens.Jwt, Version=5.1.4.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">      <HintPath>..\packages\System.IdentityModel.Tokens.Jwt.5.1.4\lib\net451\System.IdentityModel.Tokens.Jwt.dll</HintPath>
 </Reference>

      

        
        
        
      

    

I can't see assemblies in the GAC for deletion

C:\Program Files (x86)\Microsoft Visual Studio 11.0>gacutil /u System.IdentityMo
del.Tokens.Jwt
Microsoft (R) .NET Global Assembly Cache Utility.  Version 4.0.30319.17929
Copyright (c) Microsoft Corporation.  All rights reserved.

No assemblies found matching: System.IdentityModel.Tokens.Jwt
Number of assemblies uninstalled = 0
Number of failures = 0

      

        
        
        
      

    

I tried cleaning, rebuilding, reloading, deleting / bin and / lib and rebuilding and I'm fine. Personally, it might not be System.IdentityModel.Tokens.Jwt as such, but the guide I need to troubleshoot such as type load errors. I tried the .Tokens package specifically and indeed all packages:

nuget install packages.config

      

        
        
        
      

    

I still get the error, not on assembly, but only when executing:

Server Error in '/' Application.

Could not load type 'System.IdentityModel.Tokens.JwtSecurityToken' from assembly 'System.IdentityModel.Tokens.Jwt, Version=5.1.4.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: System.TypeLoadException: Could not load type 'System.IdentityModel.Tokens.JwtSecurityToken' from assembly 'System.IdentityModel.Tokens.Jwt, Version=5.1.4.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'.

Source Error: 


Line 12:     protected void Application_Start(object sender, EventArgs e)
Line 13:     {
Line 14:       GlobalConfiguration.Configure(WebApiConfig.Register);
Line 15:     }
Line 16: 

Source File: C:\Dev\Git\Connect-Applications\ControllerlessApp\src\Connect.Rest.MainApp\Global.asax.cs    Line: 14 

Stack Trace: 


[TypeLoadException: Could not load type 'System.IdentityModel.Tokens.JwtSecurityToken' from assembly 'System.IdentityModel.Tokens.Jwt, Version=5.1.4.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'.]
   System.Reflection.RuntimeAssembly.GetExportedTypes(RuntimeAssembly assembly, ObjectHandleOnStack retTypes) +0
   System.Reflection.RuntimeAssembly.GetExportedTypes() +31
   Plex.Web.UI.ServiceResolverDefaults..ctor() +842

[TargetInvocationException: Exception has been thrown by the target of an invocation.]
   System.RuntimeTypeHandle.CreateInstance(RuntimeType type, Boolean publicOnly, Boolean noCheck, Boolean& canBeCached, RuntimeMethodHandleInternal& ctor, Boolean& bNeedSecurityCheck) +0
   System.RuntimeType.CreateInstanceSlow(Boolean publicOnly, Boolean skipCheckThis, Boolean fillCache, StackCrawlMark& stackMark) +138
   System.Activator.CreateInstance(Type type, Boolean nonPublic) +105
   System.Activator.CreateInstance(Type type) +12
   Plex.Activation.AssemblyDefaultRegistrationConvention.Process(Type type, Registry registry) +118
   StructureMap.StringExtensions.Each(IEnumerable`1 enumerable, Action`1 action) in c:\BuildAgent\work\767273992e840853\src\StructureMap\Extensions.cs:10
   StructureMap.StringExtensions.Each(IEnumerable`1 enumerable, Action`1 action) in c:\BuildAgent\work\767273992e840853\src\StructureMap\Extensions.cs:10
   StructureMap.Graph.AssemblyScanner.ScanForAll(PluginGraph pluginGraph) in c:\BuildAgent\work\767273992e840853\src\StructureMap\Graph\AssemblyScanner.cs:248
   StructureMap.Graph.PluginGraph.Seal() in c:\BuildAgent\work\767273992e840853\src\StructureMap\Graph\PluginGraph.cs:121
   StructureMap.PluginGraphBuilder.Build() in c:\BuildAgent\work\767273992e840853\src\StructureMap\PluginGraphBuilder.cs:72
   StructureMap.Container..ctor(Action`1 action) in c:\BuildAgent\work\767273992e840853\src\StructureMap\Container.cs:25
   Plex.Activation.ServiceResolverBuilder.Initialize(ApplicationContext context) +288
   Connect.Rest.Framework.Hosting2.Infrastructure.AppDomainSharedServices.get_ServiceResolver() +1373
   Connect.Rest.Framework.Hosting2.WebApiConfig.Register(HttpConfiguration config) +80
   System.Web.Http.GlobalConfiguration.Configure(Action`1 configurationCallback) +63
   Connect.Rest.MainApp.WebApiApplication.Application_Start(Object sender, EventArgs e) in C:\Dev\Git\Connect-Applications\ControllerlessApp\src\Connect.Rest.MainApp\Global.asax.cs:14

[HttpException (0x80004005): Exception has been thrown by the target of an invocation.]
   System.Web.HttpApplicationFactory.EnsureAppStartCalledForIntegratedMode(HttpContext context, HttpApplication app) +544
   System.Web.HttpApplication.RegisterEventSubscriptionsWithIIS(IntPtr appContext, HttpContext context, MethodInfo[] handlers) +186
   System.Web.HttpApplication.InitSpecial(HttpApplicationState state, MethodInfo[] handlers, IntPtr appContext, HttpContext context) +172
   System.Web.HttpApplicationFactory.GetSpecialApplicationInstance(IntPtr appContext, HttpContext context) +402
   System.Web.Hosting.PipelineRuntime.InitializeApplication(IntPtr appContext) +343

[HttpException (0x80004005): Exception has been thrown by the target of an invocation.]
   System.Web.HttpRuntime.FirstRequestInit(HttpContext context) +579
   System.Web.HttpRuntime.EnsureFirstRequestInit(HttpContext context) +112
   System.Web.HttpRuntime.ProcessRequestNotificationPrivate(IIS7WorkerRequest wr, HttpContext context) +716