This question has been asked before on this forum with no real answer and I can't find any results online. I am try to write a plugin which includes the IronPython.dll to do some python execution. I have included the dll in my plugins folder however ksp is unable to load it throwing several exceptions similar to the following. AssemblyLoader: Exception loading 'IronPython': System.Reflection.ReflectionTypeLoadException: The classes in the module cannot be loaded. at (wrapper managed-to-native) System.Reflection.Assembly:GetTypes (bool) at System.Reflection.Assembly.GetTypes () [0x00000] in <filename unknown>:0 at AssemblyLoader.LoadAssemblies () [0x00000] in <filename unknown>:0 Additional information about this exception: System.TypeLoadException: Could not load type 'IronPython.Compiler.Ast.Node' from assembly 'IronPython, Version=2.7.0.40, Culture=neutral, PublicKeyToken=7f709c5b713576e1'. System.TypeLoadException: Could not load type 'IronPython.Compiler.Ast.DynamicConvertExpression' from assembly 'IronPython, Version=2.7.0.40, Culture=neutral, PublicKeyToken=7f709c5b713576e1'. System.TypeLoadException: Could not load type 'IronPython.Compiler.Ast.DynamicGetMemberExpression' from assembly 'IronPython, Version=2.7.0.40, Culture=neutral, PublicKeyToken=7f709c5b713576e1'. I have no idea how to get around this problem. Is there some way of loading non unity plugin dll's into Unity that I don't know of?