Cisco Agent Desktop user is not able to login to CUCM,
Please do following steps.
1. login to CUCM
2. User Management - Application User
3. Select the User ID that associate with Agents
4. Look for the "Available Devices" and add the device to "Controlled Devices"
5. Go to "End User" and add the End user with the phone
6. add extension and add IPCC on user's phone
After these steps, you are able to add agents to RmCm as well