The AVMCU was not able to stay connected to the Front End over the C3P channel (HTTPS Connection). The Audio-Video Conferencing ...

The AVMCU was not able to stay connected to the Front End over the C3P channel (HTTPS Connection). ���

The Audio-Video Conferencing Server failed to send C3P notifications to the focus at %1. 
Failure occurrences: %2, since %3.
Cause: The Front End may not be running correctly or may be unreachable over the network (broken HTTPS connection) from the MCU. Unavailability of the C3P channel affects conference controls, and can also prevent users from joining, starting conferences.
Resolution:
Verify that the Front End is running correctly and network connectivity and an HTTPS Connection can be established between the MCU and the Front End.