title: Could not find android.jar for API Level . Xamarin
body: <p>When I want to start my project I have a mistake </p>
  
  <p>Severity    Code    Description Project File    Line    Suppression State
  Error       Could not find android.jar for API Level . This means the Android SDK platform for API Level  is not installed. Either install it in the Android SDK Manager (Tools > Open Android SDK Manager...), or change your Xamarin.Android project to target an API version that is installed. (C:\Program Files (x86)\Android\android-sdk\platforms\android-\android.jar missing.) myproject.CrossPlatform.Droid</p>
  
  <p>I read the same mistake and there has a decision to install old verion of Visual Studio. Maybe is another way to fix it??? Cuz to install old version it is a problem.          </p>