|Component:||Microsoft Exchange Transport|
|Message:||This is an SMTP protocol warning log for virtual server ID <number>, connection #<number>.The remote host “<%3>“, responded to the SMTP command “<name>” with “<error message>“.The full command sent was “<name>“. This may cause the connection to fail.|
This event is logged when the Exchange server sends an SMTP command to a remote server and receives a response that is not valid. The virtual server ID indicates which SMTP virtual server issued the command. The remote host indicates the fully qualified domain name of the remote server that responded to the command. The actual command issued, and the response received, are also mentioned in the event.
Possible causes for this event include faulty network card drivers and network cards that are configured incorrectly.
To resolve this error, try one or more of the following:
For additional information that may help you resolve this problem, see Microsoft Knowledge Base article 153119, XFOR: Telnet to Port 25 to Test SMTP Communication.