We have Content Analysis with SNMPv2 enabled.
We get a Warning message saying:
Service: SNMP-Bluecoat-CAS-License_Check; Status: "UNKNOWN ; Status Information: No such instance currently exists in the OID (OID=.1.3.6.1.4.1.14501.8.1.4.1.6.0)"
The SNMP-Bluecoat-CAS-License_Check applies not to the Base license (which has no expiry) but to the Antivirus licenses (Kaspersky, Sophos or Mcafee).
Check that the customer has an antivirus available on his CAS (System -> Licensing).
If there are none available, then this warning will occur.