Why the "bounces" ?

[Louis-Alain Richard]

Here is the message I have from the Audifans server about once a week :

SNIP
Your membership in the mailing list quattro has been disabled due to
excessive bounces The last bounce received from you was dated
26-Nov-2006.  You will not get any more messages from this list until
you re-enable your membership.  You will receive 3 more reminders like
this before your membership in the list is deleted.

To re-enable your membership, you can simply respond to this message
(leaving the Subject: line intact), or visit the confirmation page at
SNIP

Louis-Alain



-----Message d'origine-----
De : Jason Kohls [mailto:jasonkohls at gmail.com] 

Please define "bounces" issue -- are these real bounces you're receiving i.e.
550 5.7.1 Unable to relay or 550 5.1.1 User unknown or something
entirely different.