title: Xamarin build Error The "XamlCTask" task has been declared or used incorrectly
body: <p>I downloaded some exercise files from LinkedIn Learning. I'm trying to build the project from the files I downloaded and I get this error message:</p>
  
  <pre><code>Error The "XamlCTask" task has been declared or used incorrectly, or failed during construction. 
  Check the spelling of the task name and the assembly name. 
  </code></pre>
  
  <p>I have no idea what it's talking about. It also doesn't tell me much about where the error is occurring like a file name or code line so that's not very helpful. The only thing I have to go off of is that it's in the shared project. I also tried searching the entire solution for the text "XamlCTask" and it returned 0 results. What I've tried so far:</p>
  
  <ul>
  <li>Clean solution</li>
  <li>Rebuild solution</li>
  </ul>
  
  <p>Any ideas on how to resolve this error?</p>