No 'Best Before End' on cookies

[Anon]

I'm puzzeled that helpful info on PHP and cookies is so hard to find, or maybe I'm not looking in the right places...

I'm making a flat-file forum, and for the login procedure I'm trying to provide users the ability to be remembered for 10 years(!), but even if you check the option to extend the the life of the cookies, you are still required to login again at a later time.
Anyone care to tell me what I'm doing wrong?

if ($expiredate == "check") { $bestb4end = "315360000000"; / 10 years / }
else { $bestb4end = "3600"; / 1 hour / }

setcookie ("FORUMname", "$username", time()+$bestb4end, "$forumroot", "$siteurl", 0);

[[deleted]]

Cookies are tricky because some browsers want different formats.
Check the annotations in the PHP manual on the setcookie() function.