After the latest .NET framework update I see those errors in the browser console:
GET http://ajax.aspnetcdn.com/ajax/4.5.1/1/MicrosoftAjaxWebForms.debug.it.js 404 (Not Found)
GET http://ajax.aspnetcdn.com/ajax/4.5.1/1/MicrosoftAjax.debug.it.js 404 (Not Found)
Any hint? Thanks in advance