Phones Show no service Message

If your phones are showing no service, this means your phone is unable to reach UGS via the internet to register the device for calls. 

To resolve this follow the steps below.

Step 1. Restart your internet by rebooting your isp modem/gateway. by removing power cord for 30 seconds and then plug back into power source.  If this doesnt resolve issue after 2 minutes and other devices can reach internet proceed to step 2.

Step 2. Ensure that your phone is being assigned a local ip. Check yealink devices by pressing menu on home screen and select status. and then select IPV4. It should have an private ip (, or If you dont have an ip from one of the 3 ranges your phone isnt being assigned an ip from your dhcp server/isp router/firewall. Check dhcp server on your network to ensure that it has ips available in pool to assign. If no ips available increase ip pool on server. If available ips proceed to next step.

Step 3.  Move phones to working network jack to see if they can obtain an ip from another location to verify not an issue with phone network port. If phone gets an ip at another location. Check wiring/switchport at original location. 

Step 4. If your phones have an valid ip ensure that you can reach and properly and get replies without packet loss when pinging out to that url and ip. If you dont get replies back Check with isp for network issues.