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SMTP Protocol Events

SMTP Protocol Events

SMTP protocol events occur when SMTP protocol commands are received or transmitted over the network. The supported events fall into two broad categories:

  • In-bound Protocol Events Events occur when an external agent initiates a connection with the SMTP service and executes an SMTP dialog. Two events are associated with this dialog: OnInBoundCommand, and OnServerResponse.
  • Out-bound Protocol Events Events occur when the SMTP service initiates a connection with another SMTP service in order to relay messages. There are five events associated with this dialog: OnSessionBegin, OnMessageStart, OnPerRecipient, OnBeforeData, and OnSessionEnd.