Postfix mail queue is empty but emails keep coming

The messages that have been sent or are trying to be sent are stored in /var/spool/mqueue. Messages that Sendmail has not tried to queue yet can be found in /var/spool/mqueue-client.

So try this (I assume you want to get rid of all messages in the queue):

• Stop sendmail
• rm /var/spool/mqueue/*
• If you want to remove messages in waiting, rm /var/spool/mqueue-client/*.
• Start sendmail

This will clear our your queue folder(s) until the system receives another message. You can double check by running mailq (both queue folders), or sendmail -bp (only the queue folder).

NOTE: With most Linux distributions you can start/stop services with with service sendmail <start|stop|restart> or /etc/init.d/sendmail <start|stop|restart>. Both options have many other status flags which can be observed by typing in the command and service without the status flags.

If they are empty, it probably won't hurt to delete them. Not sure why there are empty files in your queue, could be any number of reasons. When you delete them, make sure you use postsuper -d <queue_id>.