Can't Receive Calls
Learn how to troubleshoot your IP phone if you're unable to receive calls. Updating the NAT setting will often resolve the issue.
Learn about Ghost Calls and how you can prevent them on your Telzio phone system.
Remote Desktop Support
Get remote desktop support for your Telzio phone system.
The maximum recommended ping time for using Telzio to place voice calls is 150 ms. If your ping tests out at higher than 150ms, you will need to contact your internet service provider to determine the cause of the problem.
Ports and IP Addresses
Overview of port ranges and IP addresses used by Telzio.