Just hit **# on the keypad and the CIPCwill enable the button in settings for a factory reset. Sometimes the phone may run into issues or may be unable to register to another tftp server (eg. another CME or CUCM server) due to a bug or maybe due to the security settings tying it to a specific server.
Step 1 - Click Settings
Step 2 - Hit "**#"........
The strange thing is that usually the first install or two will work on any new machine but then it suddenly won't. I had this experience on QEMU 2.13 on a different machine. There is something finicky or buggy about the CUCM installer even when choosing the same virtual hardware specs.
qemu-kvm command:
/usr/libexec/qemu-kvm -version
QEMU PC emulator version 0.12.1 (qemu-kvm-0.12.1.2-2.506.el6_10.1), Copyright (c) 2003-2008 Fabrice Bellard
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