I a looking for a way to receive data from a serial device and populate a textbox with the value in my .aspx page. For example: I have an electronic RFID reader attached to my serial port, when I scan an electronic ID button I need the number value of that button to populate a textbox. I would like to do this without any third party software. I found an example VB.Net application that does this but I can't seem to make it work in my asp.net application. You can download the example here: http://corcav.www1.dotnetplayground.com/cc/VBNetRs232.htm