Hello,
the corresponding Enterprise Parameters URL is only used for phone models 7940/7945/7960/7965/7970 (you can verify that by selecting the URL Parameter).
For all other IP Phone models, the Corporate Directory URL is handled by the "Corporate Directory" IP Phone service. There, you should fill-in the URL (http://<CUCM_IP>:8080/ccmcip/xmldirectoryinput.jsp or hostname in your case). Also, note that for firmware versions 9.3.3 and later you should use HTTPS.
Georgios.
Georgios
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