I also experienced the same issue (CF_RESOURCE_OUT_OF_SERVICE) when a specific user try to go Ready on Finesse.I tried multiple troubleshooting without success until I restarted the CTIManager service on the Pub (server that the phone was registered ...
I had the same problem, phones were showing 'unregistered' in cucm but the actual phone was working and able to make calls.
I restart the "Cisco RIS Data Collector" in Serviceability and this fixed the problem.
I was also getting this error message
"Failed to authenticate with the device at ip.ip.ip.ip using TELNET. TELNET access is required for access to voice configuration. Cannot continue. Exiting CCA.
Trying to use Cisco Configuration Assistance to wor...
I installed the .exe file and had the network setting grayed out. I unistalled that and reinstall the .msi and keep having the same problem. I still had the .msi installed and close it out and then run it as Administrator , it took few seconds to re...