Is your client able to resolve the CM FQDN properly and are you running a DP A.08.00 GUI? Have you added an entry to the /etc/opt/omni/server/users/UserList for your client and user?
Point a web browser to the following site https://<cm-hostname>:7116
It will ask whether it is allowed to continue, then a click on the certificate symbol just before or after the address bar, will show you the certificate. This way you can see whether the certificate is expired
Regards,
Sebastian
