>Like William I use Form Authentication too. But I use cookies in my ASP.NET app; not for authentication but for other purpose.

Thanks, could you elaborate on Form Authentication. I just would like to verify if this is the same as what I already tried a few years ago.

As for the usage of cookies elsewhere, do you have problem with browsers blocking cookies, where you have to either drop the cookie security at the browser level or add your Web site in the list of Trusted sites? Because, this is the major issue right now with the usage of cookies. There are so many browser installation, or those that would increase their security after a while, making it that the cookie is intercepted by the browser and rejected.