ssh -Y no longer works

[Gene Heskett <gheskett@wdtv.com>]

Greetings everyone;

For the past decade and change, when I wanted to do a poweroff code 
test/preview, I have been able to open an sss -Y machinename session and 
start a graphical heavy program with all the X stuff sent back to this 
big iron machine with a nice comfy chair in front of the keyboard.

But I updated this machine to wheezy, debian 7.8, a couple months back 
and hadn't had a good excuse to do that, although I had been able to run 
a session of update-manager by that means.

I just tested that again, it works from the shop machine which is based 
on the ubuntu 10.04-4 LTS install, but not from the lathes machine which 
has a new install on it that is, with the exception of a pinned kernel, 
pretty much straight wheezy and updated daily.

The error I get when I attempt to run via this ssh -Y machinename link, a 
session of update-manager is:

gene@lathe:/lib/firmware$ sudo update-manager
[sudo] password for gene: 
X11 connection rejected because of wrong authentication.
/usr/lib/python2.7/dist-packages/gtk-2.0/gtk/__init__.py:57: GtkWarning: 
could not open display
  warnings.warn(str(e), _gtk.Warning)
X11 connection rejected because of wrong authentication.
[   ERROR:UpdateManager.BugHandler] No exception handler installed.
Traceback (most recent call last):
  File "/usr/bin/update-manager", line 37, in <module>
    app = Application(APP_NAME, LOCALE_DIR, frontend='Gtk')
  File "/usr/lib/pymodules/python2.7/UpdateManager/Application.py", line 
120, in __init__
    self._load_frontend(frontend)
  File "/usr/lib/pymodules/python2.7/UpdateManager/Application.py", line 
201, in _load_frontend
    "frontend", FrontendBase)
  File "/usr/lib/pymodules/python2.7/UpdateManager/Application.py", line 
240, in _load_meta
    obj = symbol(*module_args, **module_kwargs)
  
File "/usr/lib/pymodules/python2.7/UpdateManager/Frontend/Gtk/__init__.py", 
line 59, in __init__
    gtk.init_check()
RuntimeError: could not open display

When I try to run linuxcnc on either of those machines, the X display 
remoting fails, but with a slightly different error.

gene@lathe:/lib/firmware$ linuxcnc
LINUXCNC - 2.8.0-pre1-602-gfa8867a
Application initialization failed: unknown color name "BACKGROUND"
Error in startup script: can't invoke "image" command:  application has 
been destroyed
    while executing
"image create photo -file $f/$i.gif"
    invoked from within
"if [file exists $f/$i.gif] {
            return [image create photo -file $f/$i.gif]
        }"
    (procedure "linuxcnc::image_search" line 7)
    invoked from within
"linuxcnc::image_search linuxcnc-wizard"
    invoked from within
"set logo [linuxcnc::image_search linuxcnc-wizard]"
    (file "/usr/lib/tcltk/linuxcnc/bin/pickconfig.tcl" line 31)
Application initialization failed: unknown color name "BACKGROUND"

gene@lathe:/lib/firmware$ xhost
access control disabled, clients can connect from any host
INET:coyote.coyote.den
INET:lathe.coyote.den
INET:shop.coyote.den
SI:localuser:gene

So my questions is, what fixes this?

Thanks all.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Genes Web page <http://geneslinuxbox.net:6309/gene>