User Unable to Log in Cisco Personal Communicator even with the valid credential

Usually the issue can be resolved in manually downloading the user profile from Call Manager.

Enable TFTP client program on the client PC
Open Command prompt and type in tftp then enter
type the following command: tftp <Call Manager's IP> get <UPCprofilename>.cnf.xml then enter
The file will be downloaded to C:\users\<userprofile> directory
Move the file to C:\Users\<userprofile>\AppData\Local\Cisco\Unified Communications\Client Services Framework\Config
Now user should be able to log in the Personal Communicator

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