I've recently started getting more of these LDAP group query failures.
The Critical message is:
LDAP group query failure during per-recipient scanning, possible LDAP misconfiguration or unreachable server
The cisco security gateway is connected to LDAP (AD) and we have no issues with mailflow.
The weird thing is that the original email was sent in 01-Dec-2014 - the cisco ironport has resurrected the email on 23-Aug-2018 and all of a sudden started ...