If a phone loses registration, it will no longer be able to place or receive calls. Additional indicators of registration loss are:

  • Cisco
    • Line keys will glow Orange/'Amber' to indicate no active registration (Any model)
  • Polycom
    • "URL Call Disabled" is listed on the display screen when trying to place a call. (Any model)
    • Line Key Phone Icon is displayed with a diagnal cross on it. (SoundPoint IP models)
    • Line key shows a red circle with an X inside (VVX models)

If a customer's phones lose registration, verify the following:

  • Internet Connection:
    • Ensure that the phone has a stable connection to the internet. A phone could be connected to a router, applying an ethernet connection and private IP to the device, but the router may not be connected to the main source of internet (ISP gateway/modem) or there may be a general ISP connection issue causing an outage between the devices.
    • Verify that SIP ALG is disabled on all network devices used to connect the phones. See this article for specific router instructions.
  • DNS
    • Polycom phones have a very short DNS timeout setting. It's recommended to use efficient DNS servers such as Google DNS (

If the above steps did not help, contact Intermedia support.