Hi
My exchange environment consist with "Server Exchange 2010 SP3" and "Edge Server with Exchange 2010 SP3".
On Edge server in SMTP receive log i get every now and then an entry: xxxxxx 500 5.3.3 Unrecognized command.
It is serius problem because I got few e-mails from senders that they had problem with sending e-mail messages to our e-mail domain. They receive e-mail report, for example
Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the server for the recipient domain domena.plbymail.domena.pl.[95.xxx.xxx.xx].
The error that the other server returned was:
500 5.3.3 Unrecognized command
Could you help me to solve this problem? What could cause this problem?
Thank you in advance
Tomasz
Kind Regards Tomasz
