Logging SMTP Protocol Activity in Exchange 2007 / 2010

Enable protocol logging on a Receive Connector

Set-ReceiveConnector “Connector Name” -ProtocolLoggingLevel verbose

Receive Connector logs default path:

  • Exchange 2010: \Exchange Server\V14\TransportRoles\Logs\ProtocolLog\SmtpReceive
  • Exchange 2007: \Exchange Server\TransportRoles\Logs\ProtocolLog\SmtpReceive

To change:

Set-TransportServer “TRANSPORT SERVER NAME” -ReceiveProtocolLogPath “C:\Directory”

Enable protocol logging on a Send Connector

Set-SendConnector “Send Connector Name” -ProtocolLoggingLevel verbose

Send Connector logs default path:

  • Exchange 2010: \Exchange Server\V14\TransportRoles\Logs\ProtocolLog\SmtpSend
  • Exchange 2007: \Exchange Server\TransportRoles\Logs\ProtocolLog\SmtpSend

To change:

 Set-TransportServer “TRANSPORT SERVER NAME” -SendProtocolLogPath “C:\Directory”

Mail acceptance failure, BDAT command

The BDAT ESMTP command verb is an alternative to the DATA command. When an SMTP virtual server responds to the EHLO keyword with CHUNKING, the SMTP server indicates that it supports the BDAT command and will accept messages in chunks.

To resolve this error, check the messaging environment for issues or configurations that might be blocking the BDAT command verb such as:

  • Transient network outages
  • SMTP proxies
  • Firewalls
  • Applications