First, make sure you are accessing the eGauge correctly. By default, the factory credentials on the eGauge can only be used from a computer connected to the same network as the eGauge and after clicking on the LAN Access button in the top right corner of the main graph page. As a general rule, if you can see a proxy server address (http://devname.egaug.es or http://devname.d.egauge.net) the factory credentials will not work. The factory credentials are owner / default.
If these credentials do not work (for example, if they were changed in the past and you no longer remember your password), you can request a password reset from eGauge support. Simply email email@example.com with your device name and MAC address. Both pieces of information are required. Also note that your eGauge must be online and connected to the proxy server in order to perform a remote password reset. eGauge support does not have the ability to view or recover previously set passwords.
Installers can reset passwords directly through eGuard. Please see this article for more information.