No, it's not the Admins ...
As Nexus was trying to show ... the issue is "Cookies". It depends which browser you are using, how the security settings are configured, and if you have a personal firewall that may be erasing or expiring cookies. I'm using FireFox (browser) and ZoneAlarm (firewall), and depending upon which profile I use (I have several usernames on this machine), I may have to logon manually or am automatically logged on.