From: John Stone (
Date: Thu Jul 30 2020 - 00:18:24 CDT

  Your problem below isn't a OpenGL/GLX problem, but a problem with Tk
being unable to create an additional windowing system connection during
startup. I don't know anything specifically about your mobaxterm app,
but it is likely that there are issues here associated with whatever
socket forwarding mechanism it is trying to use to redirect remote
X clients to the window server. It allowed VMD to begin creating
X server connections, but then failed to allow Tk to do the same,
it may simply be a bug/limitation in mobaxterm.

Note: recent linux distributions are beginning to ship versions of
X-Windows that no longer implement network-based indirect GLX
rendering contexts, which means that you can't forward X11 OpenGL
applications through SSH tunnels on such systems.


On Sat, Jul 11, 2020 at 12:55:29PM +0530, SHRAVANI NETHI . wrote:
> Dear VMD users,
> I am trying to access my remote workstation using windows10.
> I am using mobaxterm for this so as to have inbuilt x11 forwarding.
> I am able to access matlab, gnuplot, and others but when I am trying to
> access VMD I am getting following error.
> Info) VMD for LINUXAMD64, version 1.9.3 (November 30, 2016)
> Info)
> Info) Email questions and bug reports to
> Info) Please include this reference in published work using VMD:
> Info) Humphrey, W., Dalke, A. and Schulten, K., `VMD - Visual
> Info) Molecular Dynamics', J. Molec. Graphics 1996, 14.1, 33-38.
> Info) -------------------------------------------------------------
> Info) Multithreading available, 16 CPUs detected.
> Info) CPU features: SSE2 AVX AVX2 FMA
> Info) Free system memory: 60GB (95%)
> Info) Creating CUDA device pool and initializing hardware...
> Info) Detected 1 available CUDA accelerator:
> Info) [0] Quadro P600 3 SM_6.1 @ 1.56 GHz, 2.0GB RAM, KTO, AE2, ZCP
> Warning) Detected X11 'Composite' extension: if incorrect display occurs
> Warning) try disabling this X server option. Most OpenGL drivers
> Warning) disable stereoscopic display when 'Composite' is enabled.
> Info) OpenGL renderer: Software Rasterizer
> Info) GLSL rendering mode is NOT available.
> Info) Textures: 2-D (16384x16384), 3-D (512x512x512), Multitexture (8)
> MoTTY X11 proxy: unable to connect to forwarded X server: Network error:
> Software caused connection abort
> ERROR) Tk startup error: couldn't connect to display "localhost:14.0"
> X I/O error
> Kinldy help to resolve this.
> previously I installed cygwin on my windows to have shell enviroment.
> Since, I was facing problem with X11 forwarding with cygwin, I am trying
> mobaXterm.
> -
> Thanks in advance
> sravani

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