Cant use doveadm to set ACL . [request for help]

Hi, i keep getting error for using doveadm acl get commands.

Below is the output for grep 'socket_path' :-

grep 'socket_path' /etc/dovecot/dovecot.conf auth_socket_path = /var/run/dovecot/auth-master auth_socket_path = /var/run/dovecot/auth-master

[root@mail root]# doveadm acl get -u bob@mydomain.net -S /var/run/dovecot/auth-master -m Inbox doveadm(bob@mydomain.net): Error: doveadm server sent invalid handshake: VERSION 1 1 doveadm(bob@mydomain.net): Error: /var/run/dovecot/auth-master: Internal failure for bob@mydomain.net ID Global Rights