Recently I got to work on a project which needed file uploading just like in GMail and Yahoo Mail. Before proceeding further, I would like to mention that it is not possible to use AJAX to do file uploading to ther server as JavaScript can execute only in the browser and does not have access to the file system. So the technique we employed here is the the hidden IFrame . To make this work we need JavaScript and any server side script. For the demo, I will be using ASP.NET with C# on the server side. Let us delve in to the code without further delay. Step 1: In your web application, create two aspx files UploadTest.aspx and UploadFile.aspx. Step 2: Add this HTML code inside form tag to UploadTest.aspx <table id="tblAttach"> <tr> <!--- This td displays the link Attach File--> <td id="td_upload_attach" style="DISPLAY: block;> </td> <!--This td displays the attaching message while the file is uploading to ther server--> <td ...