title: Sys.WebForms.PageRequestManagerServerErrorException: An unknown error
body: <p>I have created a text area that allows users to enter html code. When I attempt to post this code back to the server, I get a popup window that says "Sys.WebForms.PageRequestManagerServerErrorException: An unknown error occured while processing the request on the server. The status code returned from the server was: 500".</p>
  
  <p>I believe this has something to do with the fact that what I am posting back contains html.</p>
  
  <p>How do I do this safely and without causing this error message?</p>
  
  <p>Thanks!</p>