When an MTA (Mail Transfer Agent) starts an SMTP session to Encryption Management Server and stops sending data without properly terminating the session, an error can be seen in the Encryption Management Server Mail log.
ERROR pgp/messaging[24803]: SMTP-XXXXX: pgpproxy: error reading/processing message error=-11990 (read failed)
The sender MTA stops sending data to the Encryption Management Server without terminating the connection gracefully - using <CRLF>.<CRLF>
- as expected by the SMTP protocol.
This error in the Encryption Management Server Mail log shows that the sender MTA stopped sending data to the Encryption Management Server unexpectedly.
It will be necessary to analyse why the sender MTA behaves in this way.