I started receiving messages that are failing to be delivered:
Diagnostic-Code: smtp;550 5.6.11 SMTPSEND.BareLinefeedsAreIllegal; message contains bare linefeeds, which cannot be sent via DATA and receiving system does not support BDAT
These just started out of the blue. Prior to a few days ago, we never received messages like this. I am using the latest GM 2017.