This is a small tutorial with exim commands you can use with your exim mailserver:

>> Count the number of messages in the queue.
root@localhost# exim -bpc

>> Listing the messages in the queue (time queued, size, message-id, sender, recipient).
root@localhost# exim -bp

>> Print a summary of messages in the queue (count, volume, oldest, newest, domain, and totals).
root@localhost# exim -bp | exiqsumm

>> Check what Exim is doing right now.
root@localhost# exiwhat

>> Test how exim will route a given address.
root@localhost# exim -bt user@localdomain.com

>> Display Exim’s configuration settings.
root@localhost# exim -bP

>> Search the queue for messages from a specific sender.
root@localhost# exiqgrep -f [luser]@domain

>> Search the queue for messages for a specific recipient/domain.
root@localhost# exiqgrep -r [luser]@domain

>> Print messages older than the specified number of seconds. Eg: messages older than 1 hour.
root@localhost# exiqgrep -o 3600 [...]

>> Print messages younger than the specified number of seconds. Eg: messages less than an hour old.
root@localhost# exiqgrep -y 3600 [...]

>> Match the size of a message with a regex. Eg: Messages between 500-599 bytes.
root@localhost# exiqgrep -s ‘^5..$’ [...]

>> Match only frozen messages.
root@localhost# exiqgrep -z

>> Match only frozen messages.
root@localhost# exiqgrep -x

>> Print just the message-id of the entire queue.
root@localhost# exiqgrep -i

>> Start a queue run.
root@localhost# exim -q -v

>> Start a queue run for just local deliveries.
root@localhost# exim -ql -v

>> Remove a message from the queue.
root@localhost# exim -Mrm <message-id> [ <message-id> ... ]

>> Freeze a message.
root@localhost# exim -Mf <message-id> [ <message-id> ... ]

>> Thaw a message.
root@localhost# exim -Mt <message-id> [ <message-id> ... ]

>> Deliver a message, whether it’s frozen or not, whether the retry time has been reached or not.
root@localhost# exim -M <message-id> [ <message-id> ... ]

>> Deliver a message, but only if the retry time has been reached.
root@localhost# exim -Mc <message-id> [ <message-id> ... ]

>> Force a message to fail and bounce as “cancelled by administrator”.
root@localhost# exim -Mg <message-id> [ <message-id> ... ]

>> Remove all frozen messages.
root@localhost# exiqgrep -z -i | xargs exim -Mrm

>> Remove all messages older than five days (86400 * 2 = 172800 seconds).
root@localhost# exiqgrep -o 172800 -i | xargs exim -Mrm

>> Freeze all queued mail from a given sender.
root@localhost# exiqgrep -i -f user@example.com | xargs exim -Mf

>> View a message’s headers.
root@localhost# exim -Mvh <message-id>

>> View a message’s body.
root@localhost# exim -Mvb <message-id>

>> View a message’s logs.
root@localhost# exim -Mvl <message-id>

>> Add a recipient to a message.
root@localhost# exim -Mar <message-id> <address> [ <address> ... ]

>> Edit the sender of a message.
root@localhost# exim -Mes <message-id> <address>