---- dataentry configoptions ----
type             : variable
name             : $bounce_mailbox_purge_unprocessed
purpose          : Delete bounces from the mailbox that were not matched to be for a campaign or subscriber (unidentified bounce)
allowed          : true false 0 1
default          : true
status_s         : 
category         : bounce management
----

It is best to set this to true. The bounce will be added to the phpList database, so you can view it in the phpList admin pages.