ssh -X (-Y) not working

[Karl Pearson <karlp ourldsfamily com>]

I like remote managing my server using ssh -X or ssh -Y and then running 
gui apps sometimes.

I've check workstation and server X11Forwarding yes and then restarted 
sshd so don't know where else to go.

I've checked the logs and there's nothing about it. The error I get is:

[root mail root]# system-config-printer
system-config-printer: could not open display
This is a graphical application and requires DISPLAY to be set.

or:

[karlp mail ~/]$ xterm
xterm Xt error: Can't open display:
xterm: DISPLAY is not set

Of course, the obvious is to set $DISPLAY, which doesn't work either.

I've seen blogs, threads and other stuff all over the net and everything 
says, enable X11Forwarding. I've done this for years and have never had 
that not work. Using -X or -Y should even countermand that setting if it's 
off, right?

Any ideas where to go next?

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 _/   _/ arl _/_/_/  _/ earson    KarlP ourldsfamily com
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