Error “psa dead but subsys locked” is shown when check status of Parallels Plesk Panel from the command line

~# /etc/init.d/psa status
psa dead but subsys locked
~#

Resolution

~# rm -f /var/lock/subsys/psa
~# /etc/init.d/psa start1
Starting Plesk...                                                     done
~#

Further information: http://kb.parallels.com/6566