title: Problem with "Value cannot be null. Parameter name: key" in tfs site server
body: <p>I have a problem with my site TFS when I click on my project on site:</p>
  
  <blockquote>
    <p>Value cannot be null. Parameter name: key</p>
  </blockquote>
  
  <p><a href="https://i.stack.imgur.com/eHZQV.png" rel="noreferrer"><img src="https://i.stack.imgur.com/eHZQV.png" alt="this is image error"></a></p>
  
  <p>I tried to find a solution to fix, but couldn't. 
  I hope that anyone can help me.</p>
  
  <p>Thank you very much and regards.</p>