One or more OfficeScan agents do not have a valid OfficeScan server certificate.
This is because the OfficeScan agent and server have mismatched certificate, possibly because you have pointed the agent at a different server, or reinstalled the OfficeScan server.
There are two ways to fix this. You can either reinstall OfficeScan on each agent without a valid server certificate, or run the following command on each agent:
IpXfer_x64.exe -e OfcNTCer.dat
❗ If you are running OfficeScan XG instead of OfficeScan 11, run this command: IpXfer_x64.exe -e OfcNTCer.dat -pwd [unload password]
The IpXfer_x64.exe program can be found in \\OfficeScanServerName\ofcscan\Admin\Utility\IpXfer\.
The OfcNTCer.dat file (which contains the correct server certificate) can be found in \\OfficeScanServerName\ofcscan\Pccnt\Common\.
After running this command (which has no GUI) on each client, the OfficeScan agents should all have valid server certificates. You can confirm this by trying to update the OfficeScan client or checking that the One or more OfficeScan agents do not have a valid OfficeScan server certificate message has disappeared.