The following recipient(s) could not be reached:
username@xxxxxxxxxxx on 24/10/2006 10:33 AM
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<srv.example.ca #5.5.0 smtp;550 Service unavailable; Client host [184.108.40.206] blocked using 88.blacklist.zap; Mail From IP Banned>
<Note: the real domains and IP addresses were replaced in the error>
I will contact the recipients email administrator to see if they know!