I have a situation where existing Cisco Secure Endpoint connectors/agents are not able to upgrade. On most of the connectors, the error reported in the console is mentioned here https://www.cisco.com/c/en/us/support/docs/security/secure-endpoint/217687-problem-solution-secure-endpoint-portal.html, it is the same error code (3240165382 - Download verification failed) as in the article. As far as I can tell these connector's host are showing up in our AD environment. What other issues could cause this error code?