The mail queue is where mail is put before it is processed for local or remote delivery. The mail queue typically operates smoothly without interaction but every once in a while, the server administrator may need to take action to unclog it. This typically happens in a scenario where either a malicious user is spamming from a local address to remote servers or a remote server is spamming users on a local domain.
You will often want to change to the clogged queue to see what messages are in the queue.
Then, you will want to actually see the contents of messages if you can't determine if a message is spam from the sender/recipient.
Expiring a message will result in the message being deleted the next time the mail queue is processed. Normally messages in the queue will expire after 1 week but you may wish for that time to be shorter on a given message.
The following procedures will explain how to delete message(s) from the mail queue. Deleting a message immediately removes the message from the queue and no further attempts to deliver the message will occur.
The following procedures will explain how to purge (delete) messages from the local, remote, and todo mail queues. If a queue is purged, it will not be processed in any way. Messages must exist in the queue you wish to purge from. Purging is a last-ditch effort to clear a queue of messages you don't want processed.