If you visit Asp.net Ajax Forum, you will find hundreds of request on File Upload Control that it does not give Ajax version of the page when it is placed in an UpdatePanel. Certainly, it is not possible, as the XMLHTTPRequest object that is used internally to post the form does not support file upload....

The jQuery BlockUI Plugin lets you simulate synchronous behavior when using AJAX, without locking the browser[1]. When activated, it will prevent user activity with the page (or part of the page) until it is deactivated. BlockUI adds elements to the DOM to give it both the appearance and behavior of...