I am getting this error while sending mail to my local domain and other domain also receive the same error msg when they send mail to our domain.
Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this error. The error that the other server returned was: 502 502 5.5.2 Error: command not recognized (state 9).
I have checked my dns configuration and also check through telnet from outer domain, its working fine.
Thanks and Regards