Phone.com provisions their Polycom phones to have the web interface disabled.
We highly recommend calling their technical support to get this interface opened up. If you have trouble and you wish to circumvent their provisioning, you can follow the steps below:
1. Reset Phone To Factory (do this from the menu buttons)
2. Navigate to the webadmin page and login: Username: admin | Password: 456
3. Follow the instructions here: Polycom Deskphone Configuration
4. Set the provisioning server to https://polycom.prov.phone.com, admin and blank. Your phone will reboot. (If not, reboot manually)