The issue that was causing the error below has now been resolved.
"The domain $noSPFdomain is restricted due to NO or WRONG SPF record on the DNS. Please make there is only one SPF TXT record that starts with v=spf1 and should have include:emailsrvr.com . Multiple records must be merged into one. By not having a SPF record, the receiving email system could quarantine or reject your email messages. This is a 2 hour restriction, but this check will be done multiple times a week. (ZD/768ECC3) (in reply to end of DATA command)"