Arguably belatedly, I made the transition from Tiger to Leopard on my various machines yesterday. In general, the transition seemed to go smoothly; however, some bumps have been encountered with X11 (Xquartz 2.1.5 - (xorg-server 1.3.0-apple22) (2.1.5)). A partial work-around to start-up issues resolved ( http://lists.macosforge.org/pipermail/xquartz-dev/2009-March/002204.html), I am now running into remote connectivity issues. I am not using SSH X11 forwarding, DISPLAY seems to be correct on both sides of the connection, all four combinations of X11.app security settings seem to have no impact and neither xhost nor xhost + seem to work: aesop% echo $DISPLAY /tmp/launch-3n3Zy2/:0 % ping -c 2 fenster.local PING fenster.local (192.168.1.14): 56 data bytes 64 bytes from 192.168.1.14: icmp_seq=0 ttl=128 time=0.796 ms 64 bytes from 192.168.1.14: icmp_seq=1 ttl=128 time=0.290 ms aesop% xhost + access control disabled, clients can connect from any host aesop% slogin fenster.local fenster.local's password: Last login: Wed Mar 18 19:32:47 2009 from 192.168.1.2 fenster% echo $DISPLAY 192.168.1.2:0.0 fenster% ping aesop.local 56 2 PING aesop.local. (192.168.1.2): 56 data bytes 64 bytes from 192.168.1.2: icmp_seq=0 ttl=64 time=0 ms 64 bytes from 192.168.1.2: icmp_seq=1 ttl=64 time=0 ms fenster% xemacs & X server not responding : "192.168.1.2:0.0" aesop% grep X11 /etc/ssh* ~/.ssh/* /etc/ssh_config:# ForwardX11 no /etc/ssh_config.system_default:# ForwardX11 no /etc/sshd_config:#X11Forwarding no /etc/sshd_config:#X11DisplayOffset 10 /etc/sshd_config:#X11UseLocalhost yes /etc/sshd_config:# X11Forwarding no /etc/sshd_config.system_default:#X11Forwarding no /etc/sshd_config.system_default:#X11DisplayOffset 10 /etc/sshd_config.system_default:#X11UseLocalhost yes /etc/sshd_config.system_default:# X11Forwarding no fenster% grep X11 /etc/ssh* ~/.ssh/* /etc/ssh_config:# ForwardX11 no /etc/sshd_config:#X11Forwarding no /etc/sshd_config:#X11DisplayOffset 10 /etc/sshd_config:#X11UseLocalhost yes /etc/sshd_config:# X11Forwarding no This all worked OK under Tiger. Any thoughts on what I might be missing or miss-setting here? Thanks, Grant