Failed Mail is an email message which has, for one reason or another, been
unable to reach the intended destination and has been returned. The
message usually has some information included to say why the email could
not be delivered; for example, the email address doesn't exist, the
destination server was not available for three days; the destination server
rejected the message for some reason, etc.
Efficient handling returned messages is essential to any list server
product. Consider the following situation:
A company has a mailing list with 1,000,000 addresses on it and posts a
message to it each year. Typically addresses on a mailing list change at
the rate of 5% per month, so after one year, about 50% of the addresses
will have changed. So each year, when the company posts a message to its
1,000,000 members, it can expect 500,000 to be returned. Experience shows
that about 95% of these will return within minutes of posting. So with a
high performance list server, something like 450,000 messages may be
returned within an hour of posting.
There is no way that any human operator could manage these returned
messages (if a human could remove one address per minute, it would take
over five man years!) Clearly, managing these returned messages
efficiently is extremely important. When a message is returned, the
software must identify the failed address and place a mark against the
member's record so that no messages are sent in future.
By using high performance, batch processing, GMS Communication Server is able to
efficiently manage to removal and suspension of members when messages are