The phones are not reaching the TFTP server holding the firmware + configuration files. Setup a DHCP server with Option 150 = CUCM IP address and follow the factory setting reboot process again.

Hi, I had the same issue. You need to setup a DHCP server with Option 150 pointing to a TFTP server which holds the firmware + configuration files for your phone acording to the protocol used (SIP or SCCP). I installed windows server 2008 R2, setup D...