The RCPT Command

You tell the mail server who the recipient of your message is by using the RCPT command. You can send more than one RCPT command for multiple recipients. The server will respond with a code of 250 to each command. The syntax for the RCPT is:

RCPT TO:<forward-path>

Only one recipient can be named per RCPT command. If the recipient is not known to the mail server, the response code will be 550. You might also get a response code indicating that the recipient is not local to the server. If that is the case, you will get one of two responses back from the server:

• 251 User not local; will forward to <forward-path>-This reply means that the server will forward the message. The correct mail address is returned so that you can store it for future use.
• 551 User not local; please try <forward-path>-This reply means that the server won't forward the message. You need to issue another RCPT command with the new address.