Lỗi owin No assembly found containing an OwinStartupAttribute Error
The following errors occurred while attempting to load the app. - No assembly found containing an OwinStartupAttribute. - The given type or method 'false' was not found. Try specifying the Assembly. To disable OWIN startup discovery, add the appSetting owin:AutomaticAppStartup with a value of "false" in your web.config. To specify the OWIN startup Assembly, Class, or Method, add the appSetting owin:AppStartup with the fully qualified startup class or configuration method name in your web.config.