Alright, using that I found out what was causing the issue. This is a possible bug with Plesk 12.5.
[root@web01 ~]# /usr/local/psa/bin/mail -r
[email protected]
[2015-09-10 14:31:22] ERR [util_exec] proc_close() failed ['/usr/local/psa/admin/bin/mail_responders_control' '--del-resp' '--mailname'...