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<its028@gmail.com>: host alt1.gmail-smtp-in.l.google.com[74.125.142.27] said:
421-4.7.0 [72.47.252.237 15] Our system has detected an unusual rate
of 421-4.7.0 unsolicited mail originating from your IP address. To protect
our 421-4.7.0 users from spam, mail sent from your IP address has been
temporarily 421-4.7.0 rate limited. Please visit 421-4.7.0
https://support.google.com/mail/answer/81126 to review our Bulk Email 421
4.7.0 Senders Guidelines. m8si12273476igx.42 - gsmtp (in reply to end of
DATA command)