The Symantec Management Agent (SMA) fails to register with the Notification Server.
In the Symantec Management Console go to Settings>Notification Server>Certificate Management and check the "NS web site certificate". If there is a red X icon, the the certificate is not setup correctly.
Open IIS Manager and you will see that the correct certificate is NOT bound to the correct port on the Notification Server.
Windows Server 2012 R2
Bind the correct certificate to the correct port using IIS Manager and then restart IIS.