force qmail to process mail queue

Use qmail-qstat or qmail-qread to check the messages in queue.

Run qmail-tcpok to clear out the TCP timeout table.

After that, send the "ALRM " signal to the "qmail-send" process, and Qmail will process all messages in the queue immediately:

kill -ALRM `ps ax | grep [q]mail-send | awk '{print $1}'`

resend all mails in sendmail queue

As root you can redeliver all mail in the mail server queue via:

sendmail -v -q