ASP .NET create other Session when switch to http://example.com or http://www.example.com

Question

If I type http://example.com and login to my site and close my browser, re-open it and retype http://example.com then I am logged in.

However, when I type http://example.com, login, close the browser, re-open it, type http://www.example.com then I am NOT logged in.

I do not use ASP .NET authentication classes.
I run IIS 6 with both example.com and www.example.com URLs added to "Multiple identities for this web site" in IIS.

I do not wish the current behavior. Are there other things that can be affected because of this behavior?

Answer 1

Please make sure from your domain panel that it is referring to same IP Address and code. I was having same issue and found that IP Address was different.

Answer 2

The problem is that you can't share cookies between example.com and www.example.com, due to a quirk in the cookie specification.

Instead, what you should do is pick one of the domains as your primary. Then, detect references to the other domain, and redirect users from there back to the primary. For example, you could choose www.example.com as the primary, and redirect references to example.com back to www.example.com.

That way, the authentication cookies will be present if the user tries to switch from one domain to another.