Package: xbase-clients Version: 6.9.0.dfsg.1-5bpo2 As some ordinary user I say: olaf@ridcully:~$ xhost localhost localhost being added to access control list But it does not work: ridcully:~# xterm -display :0 Xlib: connection to ":0.0" refused by server ridcully:~# xterm -display localhost:0 does not work also.