Posts Tagged ‘T-Mobile’

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 and update your E911 address (even if you previously have)