Do not use an System.Reflection.AssemblyName with only the AssemblyName.CodeBase property set. The AssemblyName.CodeBase property does not supply any elements of the assembly identity (such as name or version), so loading does not occur according to load-by-identity rules, as you would expect from the Assembly.Load(AssemblyName) method. Instead, the assembly is loaded using load-from rules. For information about the disadvantages of using the load-from context, see the Assembly.LoadFrom(string) method overload or Best Practices for Assembly Loading.