ReceiveMode is a TIdSMTPReceiveMode property that indicates the method used when handling incoming messages on the SMTP server. ReceiveMode is used in the command action handler for the SMTP DATA command verb. 

When ReceiveMode contains rmRaw, incoming mail is read from the threaded client connection using the Capture method to store RFC message data in a TStream. Using rmRaw requires that a procedure be assigned to the OnReceiveRaw event handler to allow processing the stream for email addresses in the recipient list. If OnReceiveRaw is unassigned, an EIdTCPServerError exception will be raised. 

When ReceiveMode contains rmMessage, incoming mail is read from the threaded client connection using the Capture method to store RFC message headers in a TIdMessage instance. Using rmMessage requires that a procedure be assigned to the OnReceiveMessage event handler to allow processing the TidMessage instance for email addresses in the recipient list. If OnReceiveMessage is unassigned, an EIdTCPServerError exception will be raised. 

When ReceiveMode contains rmMessageParsed, incoming mail is read from the threaded client connection using a method similar to rmMessage. rmMessageParsed sets the NoDecode property for the TIdMessage instance to the value used in the SMTP server NoDecode property. rmMessageParsed also reconciles email addresses in the recipient list to determine the addresses which are stored in the BCCList for the TIdMessage instance. Using rmMessageParse requires that a procedure be assigned to the OnReceiveMessageParsed event handler to allow processing the TIdMessage instance for email addresses in the recipient list. If OnReceiveMessageParsed is unassigned, an EIdTCPServerError exception will be raised.

TIdSMTPReceiveMode EIdTCPServerError