This is what im doing:
byte[] bytes = File.ReadAllBytes(@Application.StartupPath+\"/UpdateMainProgaramApp.exe\"); Assembly assembly = Assembly.Load(bytes); /
if you check any WinForm application Program.cs file you'll see there always these 2 lines
Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false);
you need to call as well them in your assembly. At least this is what your exception says.