I changed the server IP address (due to adding a VLAN for the phones, etc). Using Cisco SPA504G phones. 3CX 9.0.13545 So I updated each phone (I am using static IP addresses) and updated the provisioning URL on each phone to reflect the change. Obviously i updated the phone IP addresses as needed, as well as the Ext1 SIP info. The phone will then register with the server fine. However, one they power cycle or reboot, and reprovision, the Ext1 SIP info and the provisioning URL gets updated back to the old server IP address, thus not registering. Somewhere in the system, the old IP address is still present. I looked through the Advanced Settings->Custom Settings. I did find SIPDOMAIN and DEFAULTLOCALIP values showing the old IP address. I updated them to the new IP Address. Other than these values, I cannot find the old IP address on any screen. SO i don't know how the provisioning system is still setting the phones to look at the old address. Ideas?