As originally reported ​here on the mailing list, here is the backtrace obtained with abrt.

Note: contrary to the report above, when I test this only happens on KDE, and only when using "auto-start".

abrt_version:   2.0.10
cmdline:        /usr/bin/python /usr/bin/winswitch_applet --open_server_config=
executable:     /usr/bin/winswitch_applet
kernel:         3.5.2-1.fc17.x86_64
time:           Wed 29 Aug 2012 11:30:08 PM ICT
uid:            1000
username:       fedora

backtrace:
:warnings.py:29:_show_warning:ValueError: I/O operation on closed file
:
:Traceback (most recent call last):
:  File "/usr/lib/python2.7/site-packages/winswitch/client/client_base.py", line 744, in server_dir_changed
:    self.slog("evt_type=%s" % type(evt_type), monitor, d, ignored, evt_type)
:  File "/usr/lib/python2.7/site-packages/winswitch/util/simple_logger.py", line 317, in slog
:    self._write(self.log_colour, "II", self.prefix, msgsig(msg, *args))
:  File "/usr/lib/python2.7/site-packages/winswitch/util/simple_logger.py", line 231, in msgsig
:    s = msig(*args)
:  File "/usr/lib/python2.7/site-packages/winswitch/util/simple_logger.py", line 214, in msig
:    return	"("+(','.join([str(v) for v in args]))+")"
:  File "/usr/lib64/python2.7/warnings.py", line 29, in _show_warning
:    file.write(formatwarning(message, category, filename, lineno, line))
:ValueError: I/O operation on closed file
:
:Local variables in innermost frame:
:category: <class 'gobject.Warning'>
:filename: '/usr/lib64/python2.7/site-packages/twisted/internet/gtk2reactor.py'
:lineno: 277
:file: <closed file '/home/fedora/.winswitch/client/applet.log', mode 'a' at 0x7fdde6333f60>
:line: None
:message: Warning("g_object_set_qdata: assertion `G_IS_OBJECT (object)' failed",)

After upgrading a linux server to openssh 6.7, I'm no longer able to connect to it from MS Windows (winswitch 0.12.20). In the server's log I see "fatal: Unable to negotiate a key exchange method [preauth]". I have no trouble connecting to the server via putty.

It seems that this is a twisted-conch issue: ​http://twistedmatrix.com/trac/ticket/7672

However, I assume that even once that's fixed, some work will be required on winswitch's part, too, even if only to create a new build; so opening a ticker here, too.

• Add default screen size option to Settings
  
• Add combo to SessionStartDialog when used with full desktop commands or with VNC sessions
  
• Add screen-size parameter to START_SESSION protocol
  
• Handle screen size requirements in VNC and NX:
  
  • NX can just specify it with the nx/nx options
    
  • Xvnc: either specify it on command line or use xrandr to change resolution of pre-loaded sessions.