Troubleshooting phone outages

If you have noticed that your SIP phone cannot make or receive calls please do the following:

  • Check that the phone has a secure ethernet and power connection. Wiggle the cables slightly to make sure they are not loose. 
  • Check that the other end of the phone's ethernet cable is also securely plugged in. 
  • Confirm that the network the phone is plugged into has internet access. You can do this by testing another device on the network. 
  • Confirm with your network administrator that any firewalls you have are not blocking the phone's SIP access to the internet. 
  • Power cycle the phone by unplugging the power cable and waiting 10 seconds before plugging it back in.
  • Reboot the router that the phone is plugged into. 
  • If it still cannot make or receive calls after the previous steps please find your phone manufacturer's specific instructions below. 


Grandstream Phones:


  • Press the Menu key found in the middle of the arrow keys and navigate to Config > Upgrade > Config Server and check to see that the config server field says
  • If the field is blank or has a different entry, fill out the correct string using the keypad and then reboot the phone when you are done. 
  • To factory reset the phone navigate to Config > Factory Reset and confirm. 
  • Once the phone has finished its factory reset (it may reboot itself several times and the whole process will likely take a few minutes) enter the Configuration Server string as described above and reboot the phone again. 
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