Using registry key with IP address instead of hostname in below registry key:
HKEY_LOCAL_MACHINE\SOFTWARE\Symantec\CP \Validation Server
VIP Enterprise Gateway 9.10.1
The validation server may work using DNS name but Symantec recommends IP Address only. If DNS goes down or a DNS record changes, the MCP plugin will continue to use the DNS name.
Using the IP address avoids potential interruptions if there are DNS issues.
Please Note: