I keep getting asked about how to view, flush and delete messages from an Exim mail queue.

So I thought I would post the relevant commands here:

exim -M    : Force delivery of one message
exim -qf            : Force another queue run
exim -qff           : Force another queue run and attempt to flush the frozen message
exim -Mvl : View the log for the message
exim -Mvb : View the body of the message
exim -Mvh : View the header of the message
exim -Mrm : Remove message without sending any error message
exim -Mg  : Giveup and fail message to bounce the message to the Sender