Everybody who is developing with Umbraco sooner or later gets this error message:
The following errors occurred while attempting to load the app.
– The OwinStartupAttribute.FriendlyName value ‘UmbracoDefaultOwinStartup’ does not match the given value ” in Assembly ‘umbraco, Version=1.0.6092.24026, Culture=neutral, PublicKeyToken=null’.
– No assembly found containing a Startup or [AssemblyName].Startup class.
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.
This is very easy to solve. You probaply didn’t choose your umbraco projact as starting project. You can do this by right-clicking on the project in the solution explorerer and selecting “Use this a start project”. You can only do this while the solution isn’t running.
If you have any additional questions, feel free to ask them in the comments.