Ione, I am not an "expert", but if I were you, I would do a

Scan yourlist Pfizer

to the listserv address, and see who is generating this error. If you are
getting multiple errors of this nature from this person, then delete them.

My listserv expert at Ummed has our 1400+ people list set up to pick up
repeating errors, and it automatically dumps them.  THis , I believe, is a
result of some header information that instructs the listserv to delete
folks whose addresses are bouncing.

Kathleen Bruce
Owner LACTNET, TLC
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