Unable to start qmail service getting below error.
# /etc/init.d/qmail restart
Starting qmail: [FAILED]
In error log
cannot start: unable to open mutex
Cause
---------
Necessary file /var/qmail/queue/lock/sendmutex is absent.
Resolution
---------------
Create this file manually:
# touch /var/qmail/queue/lock/sendmutex
Assign them the proper ownership:
# chown qmails:qmail /var/qmail/queue/lock/sendmutex
Restart qmail service:
# service qmail start
