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exim -bpc
counts all email in the mail queue

exim -bp
mailq — The mailq is relevant as it gives your the email IDs.

exim -M emailID
force delivery of one message

exim -qf
Force another queue run

exim -qff
Force another queue run and attempt to flush frozen messages

exim -Mvl messageID
View Log for message

exim -Mvb messageID
View Body for message

exim -Mvh messageID
View Header for message

exim -Mrm messageID
ReMove message (no errors sent)

exim -Mg messageID
Give up and fail message, message bounces to sender