Please access the UCCX serviceability page and see if the Agent Monitoring service is up and running. Also on the right hand bottom side of the CAD Agent window do you see the Partial service section, if yes click on it and see what is the service which is in partial state.
Is this a UCCX high availability setup? Are all the service master ship is owned by UCCX node1 (Publisher) if not please restart the Second node so that all the services master ship is owned by Node1 and then check the behaviour.
Also please try adding the entry for hostname of the UCCX on the CAD client boxes and check.
And one more thing, why don’t you upgrade it to UCCX 8.5 SU2 because many of the CAD issues have been witnessed in the base build which were resolved in SU2.
Hope it helps.
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