Help for users

The email you recently sent to a nikrivers.com email address has been greylisted. This simply means that your email has been temporarily rejected, and your mail server has been instructed to try again in a little while. This is to prove it is not trying to send spam; most spam-sending software will not bother to resend email.

Usually, your mail server will automatically retry sending your message, but first it might send you a message to let you know there was a delay. If the message says your email server will try again later, then everything is ok. On the other hand, if it says it won’t bother trying again then you should contact your email server administrator and ask for the problem to be fixed.

If you cannot contact the administrator, or the administrator proves to be unhelpful, please send an email to postmaster@nikrivers.com detailing the problem. Email to this address is delivered immediately, without greylisting.

Help for system administrators

The nikrivers.com mail server enforces a greylisting policy. After receiving error 450 from the nikrivers.com mail server, your mail server should retry after a short while.

From Wikipedia:

The current SMTP specification clearly states that “the SMTP client retains responsibility for delivery of that message” (section 4.2.5) and “the SMTP client is encouraged to try again”, and “mail that cannot be transmitted immediately MUST be queued and periodically retried by the sender.” (section 4.5.4.1).

If you are unable to fix this issue at your end, please send an email to postmaster@nikrivers.com detailing the problem. Email to this address is delivered immediately, without greylisting.