What Could Be Causing a System.Typeloadexception

What could be causing a System.TypeLoadException?

It could be any number of things. Likely causes are:

The assembly cannot be found
An assembly that your assembly depends upon cannot be found
The assembly is found but the type isn't in it
The type's static constructor throws an exception

Your best bet is to use the Fusion log viewer to help diagnose it. Documentation is here:

http://msdn.microsoft.com/en-us/library/e74a18c4(v=vs.110).aspx

(FYI "Fusion" was the code name of the team that designed the assembly loading system; it is somewhat unfortunate that the code name ended up in the file name of the shipped product. The thing should have been called "AssemblyBindingLogViewer.exe" or some such thing.)

How to debug System.TypeLoadException errors in .NET?

The problem is that you have a mismatch in your versions. Make sure all your assemblies are compiled for .NET 4.

What could be causing a System.TypeLoadException in a Visual Studio Unit Test?

The MyClassLibrary assembly was set to x86 mode in the configuration manager. Changing this to x64 fixed it. I really wish Visual Studio would detect this and report it as a less obscure error.

How to fix An exception of type 'System.TypeLoadException'

As you can see from the exception message, AIMLbot.dll is unable to load System.Xml.

An exception of type 'System.TypeLoadException' occurred in
AIMLbot.dll but was not handled in user code

Additional information: Could not load type 'System.Xml.XmlDocument'
from assembly 'System.Xml, Version=2.0.5.0, Culture=neutral,
PublicKeyToken=7cec85d7bea7798e, Retargetable=Yes'.

You need to verify if your target framework for AIMLbot.dll can support System.Xml Version 2.0.5.0. You might have downgraded the target framework or if you are loading the assembly through

Assembly xmlAssembly = Assembly.Load("System.Xml, Version=2.0.5.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e");

You need to check the version.

System.TypeLoadException

As recommended by Hans Passan I qualified the type with the namespace, now the code works as expected

  string ns = "TcpEchoThreadServerLibrary.";

            TcpListener listener = new TcpListener(IPAddress.Any, port);
            listener.Start();
            ILogger logger = new ConsoleLogger();

            System.Runtime.Remoting.ObjectHandle objHandle =
                Activator.CreateInstance("TcpEchoThreadServerLib", ns + protocolName + "ProtocolFactory");
            IProtocolFactory protocolFactory = (IProtocolFactory)objHandle.Unwrap();

            objHandle = Activator.CreateInstance("TcpEchoThreadServerLib", ns + dispatcherName + "Dispatcher");
            IDispatcher dispatcher = (IDispatcher)objHandle.Unwrap();

            dispatcher.startDispatching(listener, logger, protocolFactory);

how to debug system typeloadexception old VS

Found it, in windows, modules we can see the libraries, dlls and pdbs that were pull through. The problem was that one pdb was being blocked from being updated.

How to deal with System.TypeLoadException in the app.xaml.cs in xamarin.forms?

Can I ask that you please

Make sure you dont have different versions of the same Nugets in your solution.
Clean & Rebuild your Project

If That doesn't work for you try delete all your obj and bin folders and rebuild.

This usually happens because of Updates or version conflicts In my case atleast.

And do you mind showing us the LoginFinal Method?

I think you can just call Login

  MainPage = new NavigationPage(new Login);