Triangle with an Exclamation Point on the screen error indicates the same underlying issues that cause URL Calling is Disabled.

  • This error message is what Polycom phones show when they have firmware or higher.
  • The older firmware 4.0.1.xxxx only showed URL Calling Is Disabled.

What The Error Means

The phone(s) do have an IP address, which means they are wired correctly. However, the phone(s) cannot reach our registration servers, usually due to a DNS timeout or other LAN-related issue.

Common Causes

DNS servers taking too long to forward Polycom's phones DNS lookup requests

This is the root cause in 80% of cases. When a Polycom phone is trying to reach out to the Intermedia server to receive registration, the phone is asking a certain DNS server for its address. If a DNS server doesn't provide the phone with the address in 2 seconds, this error will pop-up and the phone wouldn't work properly. 

Note: this is applicable only to Polycom phones, other models are not affected.

The DNS server your network uses is usually set up on the router or a gateway. We recommend using public DNS servers like Google's (primary:, secondary: or Cloudflare's (primary:, secondary: because they are known for being quick to respond. 

If you have access to your router (login and password) but are not sure how to change your DNS settings, contact Support. Otherwise, contact your IT personnel or the ISP.

Wireless interference

This is the root cause in 5% of cases. Nearby access points and wireless devices may cause wi-fi interference which leads to the phone getting disconnected or experience QoS issues. We generally do not recommend using wi-fi connection since it's known to be less reliable than a cable connection, but you can try lowering the interference by doing a site survey and switching to a different wi-fi channel. This should be addressed by the IT personnel of your company.

DHCP Race Condition

This is the root cause in 5% of cases. DHCP race appears when there are two or more DHCP servers inside the network and they both are assigning IP addresses to the devices which leads to conflicts. DHCP server is a software or a part of a device (router, gateway) that is responsible for automatically providing all the other network devices with network configuration. This can be resolved by disabling one of the DHCP servers or removing it from the network.

Broadcast Storm

This is the root cause in 3% of cases. A broadcast storm is a condition that is usually caused by a miswired/looped network cable. It has to be investigated from inside the network. 

Firewall Interfering with the Phone's traffic

This is the root cause in 3% of cases. Routers/firewalls can interfere with the traffic blocking the phones' Keep-Alive/NAT-Binding messages that keep the phone's connection open through the firewall. The best way to resolve it would be to get a router from the Recommended routers list and have it configured according to our instructions. If you have a router that is not listed as recommended, Support still might be able to configure it properly if it's marked as Serviceable in the Full Router & Gateway List By Make/Model article.

High Packet Loss or Delay

This is the root cause in 1% of cases. Packet loss is the complete loss of data packets as they travel between the phone and the server; Delay is the amount of time required for a data packet to travel from one specific point to another. Both conditions can be caused by not having enough internet bandwidth, poor ISP line condition or incompatible equipment. The issue should be investigated by your company's IT personnel and/or addressed by the ISP.

Incorrect DHCP server settings

This is the root cause in 1% of cases. In rare scenarios, the Polycom error can be caused by incorrect gateway address and/or subnet mask entered on the DHCP server. This is a local network issue and should be investigated by IT personnel. 

Another Network Issue

In other rare scenarios, the error can be caused by other local network or ISP issues that are not yet documented. All the causes listed above should be excluded before coming to the conclusion that it's something undocumented.