I have found conflicting information about dot stuffing when transmitting an email.
Can anyone clarify?
According to the SMTP standard RFC 5321, section 4.5.2:
http://tools.ietf.org/html/rfc5321#section-4.5.2
To allow all user composed text to be transmitted transparently, the following procedures are used:
- Before sending a line of mail text, the SMTP client checks the first character of the line. If it is a period, one additional period is inserted at the beginning of the line.
- When a line of mail text is received by the SMTP server, it checks the line. If the line is composed of a single period, it is treated as the end of mail indicator. If the first character is a period and there are other characters on the line, the first character is deleted.
So, from the three points of your question, the second one is right.