Notes on  BOUNCE MESSAGE 

[common] Notification message returned to sender by a site unable to
relay EMAIL to the intended Internet address recipient or the next
link in a BANG PATH (see BOUNCE, sense 1). Reasons might include
a nonexistent or misspelled username or a DOWN relay site. Bounce
messages can themselves fail, with occasionally ugly results; see
SORCERER'S APPRENTICE MODE and SOFTWARE LASER. The terms bounce
mail and barfmail are also common.

J3N Research Labs

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