Zend Server Admin UI
When your client IP changes while your Zend Server Admin UI session is still active (did not expire yet or set to never expires), you may get a fatal error about invalid Remote IP and cannot use the UI. This can happen when moving between networks and using VPN from multiple public networks.
To resume UI access and launch a new session, you need to manually delete the browser cookie 'ZS6SESSID', then reload the page. You will then be redirected to the Login page.
The elaborated guide page above has links at the bottom to address additional browsers supported by Zend Server, e.g Firefox, Internet Explorer, and Safari.