Thanks, Paul so much, really appreciate your fast reply! I returned one step back and avoided the use of NoMachine (i.e, I hooked a screen to the Linux machine directly). I got a different error when I run Fsleyes: [meena@ghine ~]$ WARNING __init__.py 596: create - GLContext callback function raised NullFunctionError: Attempt to call an undefined function glutInit, check for bool(glutInit) before calling Traceback (most recent call last): File "fsleyes/gl/__init__.py", line 590, in create File "fsleyes/main.py", line 371, in realCallback File "fsleyes/gl/__init__.py", line 377, in bootstrap File "site-packages/OpenGL/GLUT/special.py", line 333, in glutInit File "site-packages/OpenGL/platform/baseplatform.py", line 407, in __call__ NullFunctionError: Attempt to call an undefined function glutInit, check for bool(glutInit) before calling As the Fsleyes troubleshooting page suggested, I need to install *glutInit*. I followed the recommended link (http://freeglut.sourceforge. net/docs/install.php) and I followed the steps: 1- zcat freeglut-2.2.0.tar.bz2 | tar -vxf - 2- cd freeglut-2.X.X 3- LDFLAGS=-Wl,-R/usr/X11R6/lib ./configure 4- make all 5- make install Steps (1-3) was done without errors. However, in step 4 (make all), it gave me this error: make all-recursive make[1]: Entering directory `/home/meena/freeglut-2.8.0' Making all in src make[2]: Entering directory `/home/meena/freeglut-2.8.0/src' /bin/sh ../libtool --tag=CC --mode=compile gcc -DHAVE_CONFIG_H -I. -I.. -I../include -g -O2 -Wall -pedantic -MT libglut_la-freeglut_callbacks.lo -MD -MP -MF .deps/libglut_la-freeglut_callbacks.Tpo -c -o libglut_la-freeglut_callbacks.lo `test -f 'freeglut_callbacks.c' || echo './'`freeglut_callbacks.c libtool: compile: gcc -DHAVE_CONFIG_H -I. -I.. -I../include -g -O2 -Wall -pedantic -MT libglut_la-freeglut_callbacks.lo -MD -MP -MF .deps/libglut_la-freeglut_callbacks.Tpo -c freeglut_callbacks.c -fPIC -DPIC -o .libs/libglut_la-freeglut_callbacks.o In file included from ../include/GL/freeglut.h:17, from freeglut_callbacks.c:28: ../include/GL/freeglut_std.h:123:20: error: GL/glu.h: No such file or directory In file included from freeglut_callbacks.c:29: freeglut_internal.h:112:39: error: X11/extensions/XInput.h: No such file or directory make[2]: *** [libglut_la-freeglut_callbacks.lo] Error 1 make[2]: Leaving directory `/home/meena/freeglut-2.8.0/src' make[1]: *** [all-recursive] Error 1 make[1]: Leaving directory `/home/meena/freeglut-2.8.0' make: *** [all] Error 2 I did these steps as a superuser as recommended and I tried different versions of the glutInit and all gave the same error message. Unfortunately, I did not find any help online. Any direction I can try? Thanks again Paul; --Meena On Sat, Mar 24, 2018 at 6:29 AM, paul mccarthy <[log in to unmask]> wrote: > Hi Meena, > > You could try running FSLeyes with the LIBGL_ALWAYS_SOFTWARE environment > variable, e.g.: > > LIBGL_ALWAYS_SOFTWARE=1 fsleyes > > If FSLeyes works in this way, and is fast enough, then you can use this as > a solution. > > Alternately, one person has reported success in getting around this > problem by following the steps described here: > > https://wiki.x2go.org/doku.php/wiki:development:glx-xlib-workaround > > I have translated the Ubuntu 14.04 instructions to their CentOS 6.9 > equivalents here: > > https://git.fmrib.ox.ac.uk/snippets/9 > > Let me know how you get on. > > Cheers, > > Paul > > On 23 March 2018 at 21:09, Meena M. Makary <[log in to unmask]> > wrote: > >> Dear FSL experts; >> >> I am trying to run FSLeyes from "NoMachine” on Centos 6.9 and it gives me >> the following error: >> >> WARNING __init__.py 596: create - GLContext callback >> function raised RuntimeError: OpenGL 1.4 or newer is required (detected >> version: 1.2 >> Traceback (most recent call last): >> File "fsleyes/gl/__init__.py", line 590, in create >> File "fsleyes/main.py", line 371, in realCallback >> File "fsleyes/gl/__init__.py", line 315, in bootstrap >> RuntimeError: OpenGL 1.4 or newer is required (detected version: 1.2 >> >> I tried “unset LIBGL_ALWAYS_INDIRECT “, as recommended on the >> troubleshooting page (https://users.fmrib.ox.ac.uk/ >> ~paulmc/fsleyes/userdoc/latest/troubleshooting.html), and still gives me >> the same error. >> >> Any help would be much appreciated! >> >> Thanks, >> >> -- >> *Meena M. Makary, Ph.D.* >> Assistant Professor | Cairo University <http://bmes.cufe.edu.eg/> >> Postdoctoral Fellow | Yale University School of Medicine >> <http://people.yale.edu/search/meena_beshara.profile> >> Postdoctoral Associate | The John B. Pierce Laboratory >> <http://jbpierce.org/postdoctoral-associates/> >> Treasurer | OHBM Student and Postdoc SIG >> <https://www.humanbrainmapping.org/i4a/pages/index.cfm?pageid=3449> >> >> 290 Congress Avenue, New Haven, CT 06519 >> <https://maps.google.com/?q=290+Congress+Avenue,+New+Haven,+CT+06519&entry=gmail&source=g> >> +1 (475) 731-5592 <+1%20475-731-5592> >> > > -- *Meena M. Makary, Ph.D.* Assistant Professor | Cairo University <http://bmes.cufe.edu.eg/> Postdoctoral Fellow | Yale University School of Medicine <http://people.yale.edu/search/meena_beshara.profile> Postdoctoral Associate | The John B. Pierce Laboratory <http://jbpierce.org/postdoctoral-associates/> Executive Committee Member | OHBM Student and Postdoc SIG <https://www.humanbrainmapping.org/i4a/pages/index.cfm?pageid=3449> 290 Congress Avenue, New Haven, CT 06519 +1 (475) 731-5592 <+1%20475-731-5592>