T-Mobile Wifi Calling – ER081 Firewall Port Summary

    Open the following ports on your firewall:

    • TCP 5060-5061
    • UDP 4500 (aka IKE Traversal)  –  Note: This is the port the call data goes through

    Additionally, you may need to let IKE Key Exchange traffic through.

    • UDP 500

    Other errors:

    REG99 – Go to my.t-mobile.com and update your E911 address (even if you previously have)