Esmtp mail from

ESMTP (Extended Simple Mail Transfer Protocol) is a protocol used for sending and receiving email messages over the internet. When sending an email using ESMTP, the "MAIL FROM" command is used to specify the sender's email address.

The format of the "MAIL FROM" command is as follows:

MAIL FROM:<[email protected]>

Where <[email protected]> is the email address of the sender.

For example, if you want to send an email from [email protected], the "MAIL FROM" command would be:

MAIL FROM:<[email protected]>

The "MAIL FROM" command is used to specify the sender's email address, and it is typically the first command sent in an ESMTP session. The recipient's email server will use this information to verify the sender's identity and ensure that the email is not spam or malicious.

Here is an example of a complete ESMTP session:

ESMTP client: HELO example.com
ESMTP server: 250 example.com
ESMTP client: MAIL FROM:<[email protected]>
ESMTP server: 250 2.1.0 <[email protected]>... Sender ok
ESMTP client: RCPT TO:<[email protected]>
ESMTP server: 250 2.1.5 <[email protected]>... Recipient ok
ESMTP client: DATA
ESMTP server: 354 Start mail input; end with <CRLF>.<CRLF>
ESMTP client: Subject: Test email
ESMTP client: This is a test email
ESMTP client:.
ESMTP server: 250 2.6.0 Message accepted for delivery

In this example, the ESMTP client sends a "HELO" command to introduce itself, followed by a "MAIL FROM" command to specify the sender's email address. The ESMTP server responds with a "250" code indicating that the sender is okay. The client then sends a "RCPT TO" command to specify the recipient's email address, and the server responds with a "250" code indicating that the recipient is okay. The client then sends a "DATA" command to start sending the email message, and the server responds with a "354" code indicating that it is ready to receive the message. The client sends the email message, and the server responds with a "250" code indicating that the message has been accepted for delivery.