Welcome to the JavaRanch, anuja anup, IE doesn't bind to any port so its settings are irrelevant You'll need to turn off whatever software is bound to 443 and, if you want that program running, change its settings to use a different port. Consult that software's documentation for how to do that.
443 is typically reserved for HTTPS protocol. If you have IIS installed on your machine then it may be using this port. I would recommend disabling IIS (if installed) to see if this helps. Otherwise, check your services in Control > Services to see if there are any other web based applications that may be running that are binding to this port.