Not able to access ECP for new Exchange server

Hi,

I have created a new Exchange CAS server for DR site. I am not able to access ECP using the IP address / Localhost / Hostname, where it will redirect to externalurl and failed. It showed the page cannot be displayed after I key-in username and password. and the url showed https://owa.externaldomain.com/owa/auth/owaauth.dll

Thank you

Best regards,

See Keong