Alarm email is not sent out and is discarded. The Last Discard Cause is 'BOutgoingAccount could not dequeue in-memory email: 501 Syntax error in parameters or arguments'.
I/A Series G3
'Reply To' field in the Outgoing Account properties was left empty. This field specifies the contents of the 'From' field in the email that is sent.
Configure the Outgoing Account 'Reply To' field with a valid email account. In the example below (G3 version 3.7), the valid account being used is email@example.com.