SMTP Error 501 Syntax Error

Posted on 2004-11-18
Last Modified: 2010-05-18
Does the following error pertain to a specific part of an email message, like the from or reply to address, or the message content, or can it be triggered from anywhere within the message you are sending?
501 Syntax error: Line too long line by itself
Question by:wyogirl77
    LVL 11

    Expert Comment

    Greetings wyogirl77,

    According to the SMTP, the following can cause a 500 or 501 error message (line/path too long)

                text line

                   The maximum total length of a text line including the
                   <CRLF> is 1000 characters (but not counting the leading
                   dot duplicated for transparency).

                recipients buffer

                   The maximum total number of recipients that must be
                   buffered is 100 recipients.


    Author Comment

    Thank you for the information, does that mean that line that is causing the problem can occur anywhere in the entire message, also this email is only being sent to one recipient at a time so don't think the problem is with the more than 100 recipients.
    Thank you
    LVL 11

    Accepted Solution

    Yes, I would think that any line could cause this problem.

    Expert Comment

    Hi there
    501 Syntax error in parameters or arguments
    Indicates possible poor (noisy dialup) or an intermittent drop in network line connection that caused your mail client to send erroneous command to the mail server.

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    Author Comment

    Yohan thanks for the info it was part of my plain text part of the message.

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