I am trying to migrate a 7945 phone from CME 7.1 to CUCM 10.0 but haven't had much luck so far. CME phone has 8.5.3 firmware and CUCM 10.0 has 9.3.1SR3 firmware so direct firmware upgrade should work. TFTP option 150 is still pointing to production CME so I disabled the DHCP on one of the 7945 phones and manually set the TFTP to CUCM 10.0 ip address. I did the soft and hard factory reset on the phone but it wouldn't register with CUCM 10.0. I then physically connected the phone to my laptop and using tftp on my laptop upgraded the phone firmware to 9.3.1SR3 but phone still won't register to CUCM 10.0. Status messages on the phone says "TFTP timeout" and "No ITL trust installed". On the phone security->trust list->ITL file is empty. I also tried setting enterprise parameter "prepare cluster for rollback to pre-8.0" to true and restarted TFTP and TVS services. I can ping the phone from CUCM OS Admin page
Not sure what else to try any help would be much appreciated.