I\'ve tried searching the php manual and internet on how to delete cookies and I\'ve tried it the exact same way they all say:
setcookie(\"name\", \'\', 1);
set a cookie
setcookie('cookiename', $cookie_value, time() + (86400 * 30), "/"); // 86400 = 1 day
unset cookie
setcookie('cookiename', '', time() - 3600, "/");
No need to panic. Just copy function you use to set cookie and now minus the time. Do not get confuse, make it easy and clear.