Most errors you will see are related to the GUI, and rarely effect the phone service itself.

It is however important to report any errors, which ensures we can resolve the source of the issue.

Error 3 is shown when there is no specific error definition found.
Often error 3 is a browser issue and doesn't impact the phone services
Contact the Axeos support department and report after which action the error appeared.

'503 - Service Not Available' is shown when the PBX is starting up.
This message is shown when the webserver of the PBX is already running, but the management GUI is not loaded yet.
Within a couple of minutes a screen refresh should show the login screen.