title: Updatepanel stops working under proxy and it happens only in IE
body: <p>We have an updatepanel in our site and there are a number of linkbuttons in it.</p>
  
  <p>Please note that the site works fine across all browsers without proxy</p>
  
  <p>the proxy changes the url from for instance www.mysite.net to 0-www.mysite.net.edu.net it also works fine in all browsers but IE</p>
  
  <p>the issue is that under proxy and in IE8, it gives an error when clicking one of the linkbuttons, the error message is</p>
  
  <p>"Webpage error details</p>
  
  <p>User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; Tablet PC 2.0; InfoPath.1; .NET4.0C; .NET4.0E)</p>
  
  <p>Timestamp: Sun, 13 Mar 2011 20:38:58 UTC</p>
  
  <p>Message: Sys.WebForms.PageRequestManagerParserErrorException: The message received from the server could not be parsed. Common causes for this error are when the response is modified by calls to Response.Write(), response filters, HttpModules, or server trace is enabled.</p>
  
  <p>Details: Error parsing near '</p>
  
  <p>
  
  <p>I have no idea what goes wrong here, it seems that IE can't parse the response ?</p>
  
  <p>I open IE developer developer tool and it shows where the error occurs</p>
  
  <pre><code>Sys.Net.XMLHttpExecutor = function Sys$Net$XMLHttpExecutor() {
  /// &lt;summary locid="M:J#Sys.Net.XMLHttpExecutor.#ctor" /&gt;
  if (arguments.length !== 0) throw Error.parameterCount();
  Sys.Net.XMLHttpExecutor.initializeBase(this);
  var _this = this;
  this._xmlHttpRequest = null;
  this._webRequest = null;
  this._responseAvailable = false;
  this._timedOut = false;
  this._timer = null;
  this._aborted = false;
  this._started = false;
  this._onReadyStateChange = (function () {
  
      if (_this._xmlHttpRequest.readyState === 4 ) {
          try {
              if (typeof(_this._xmlHttpRequest.status) === "undefined") {
                  return;
              }
          }
          catch(ex) {
              return;
          }
  
          _this._clearTimer();
          _this._responseAvailable = true;
          try {
              _this._webRequest.completed(Sys.EventArgs.Empty);
          }
          finally {//&lt;-----------------HERE IS WHERE THE ERROR OCCURS               
              if (_this._xmlHttpRequest != null) {
                  _this._xmlHttpRequest.onreadystatechange = Function.emptyMethod;
                  _this._xmlHttpRequest = null;
              }
          }
      }
  });
  </code></pre>
  
  <p>PLEASE HELP! THANK A MILLION!</p>