I want to store the username in the cookie and retrieve it the next time when the user opens the website. Is it possible to create a cookie which doesnt expires when the browser
In addition to what Shai said, if you later want to update the same cookie use:
HttpCookie myCookie = Request.Cookies["MyTestCookie"];
DateTime now = DateTime.Now;
// Set the cookie value.
myCookie.Value = now.ToString();
// Don't forget to reset the Expires property!
myCookie.Expires = now.AddYears(50);
Response.SetCookie(myCookie);