I’m hosting multiple domains, all use gravity forms to send mail and the mail notifications work great except one.
In all the working gravity forms notifications I’m sending notifications to a gmail account. However on the site that’s not working (let’s say example.com) I’m sending an email to firstname.lastname@example.org and have setup an email account using a 3rd party email service.
The log error I see in mail.log is (email address has changed):
May 8 16:14:29 localhost postfix/smtp: BBED9C1DA1: email@example.com, relay=mx1.privateemail.com[184.108.40.206]:25, delay=0.79, delays=0.02/0.01/0.43/0.33, dsn=5.5.2, status=bounced (host mx1.privateemail.com[220.127.116.11] said: 504 5.5.2 www-data@localhost: Sender address rejected: need fully-qualified address (in reply to RCPT TO command))