We have a CentOS 6.7 server installed with Gnome 2.28.2 that is not allowing users to switch sessions.
Users can log in and click on the "Switch User" option on the menu (or "Lock Screen"). The lock screen is displayed with the options to Switch User, Cancel and Unlock, but when we click on Switch User the display becomes black and then takes us back to the same lock screen.
We have tried disabling the user list on the login screen and that didn't work. Disabling the option to Switch Users is not an option, nor is it to have users with no passwords.
We are out of ideas, any help is really appreciated!
Thank you.
Updates
This is the latest output that I can get from /var/log/Xorg.0.log (the only file that was written)
[ 77188.044] AUDIT: Mon Nov 16 20:10:39 2015: 5849: client 34 connected from local host ( uid=506 gid=506 pid=9408 )
Auth name: MIT-MAGIC-COOKIE-1 ID: 292
[ 77188.045] AUDIT: Mon Nov 16 20:10:39 2015: 5849: client 35 connected from local host ( uid=506 gid=506 pid=9403 )
Auth name: MIT-MAGIC-COOKIE-1 ID: 292
[ 77188.053] AUDIT: Mon Nov 16 20:10:39 2015: 5849: client 34 disconnected
[ 77188.111] (II) NOUVEAU(0): EDID vendor "GSM", prod id 22744
[ 77188.112] (II) NOUVEAU(0): Using hsync ranges from config file
[ 77188.112] (II) NOUVEAU(0): Using vrefresh ranges from config file
[ 77188.112] (II) NOUVEAU(0): Printing DDC gathered Modelines:
[ 77188.112] (II) NOUVEAU(0): Modeline "1920x1080"x0.0 148.50 1920 2008 2052 2200 1080 1084 1089 1125 +hsync +vsync (67.5 kHz eP)
[ 77188.112] (II) NOUVEAU(0): Modeline "800x600"x0.0 40.00 800 840 968 1056 600 601 605 628 +hsync +vsync (37.9 kHz e)
[ 77188.112] (II) NOUVEAU(0): Modeline "800x600"x0.0 36.00 800 824 896 1024 600 601 603 625 +hsync +vsync (35.2 kHz e)
[ 77188.112] (II) NOUVEAU(0): Modeline "640x480"x0.0 31.50 640 656 720 840 480 481 484 500 -hsync -vsync (37.5 kHz e)
[ 77188.112] (II) NOUVEAU(0): Modeline "640x480"x0.0 25.18 640 656 752 800 480 490 492 525 -hsync -vsync (31.5 kHz e)
[ 77188.112] (II) NOUVEAU(0): Modeline "720x400"x0.0 28.32 720 738 846 900 400 412 414 449 -hsync +vsync (31.5 kHz e)
[ 77188.112] (II) NOUVEAU(0): Modeline "1280x1024"x0.0 135.00 1280 1296 1440 1688 1024 1025 1028 1066 +hsync +vsync (80.0 kHz e)
[ 77188.112] (II) NOUVEAU(0): Modeline "1024x768"x0.0 78.75 1024 1040 1136 1312 768 769 772 800 +hsync +vsync (60.0 kHz e)
[ 77188.112] (II) NOUVEAU(0): Modeline "1024x768"x0.0 65.00 1024 1048 1184 1344 768 771 777 806 -hsync -vsync (48.4 kHz e)
[ 77188.112] (II) NOUVEAU(0): Modeline "832x624"x0.0 57.28 832 864 928 1152 624 625 628 667 -hsync -vsync (49.7 kHz e)
[ 77188.112] (II) NOUVEAU(0): Modeline "800x600"x0.0 49.50 800 816 896 1056 600 601 604 625 +hsync +vsync (46.9 kHz e)
[ 77188.112] (II) NOUVEAU(0): Modeline "1152x864"x0.0 108.00 1152 1216 1344 1600 864 865 868 900 +hsync +vsync (67.5 kHz e)
[ 77188.112] (II) NOUVEAU(0): Modeline "1680x1050"x0.0 146.25 1680 1784 1960 2240 1050 1053 1059 1089 -hsync +vsync (65.3 kHz e)
[ 77188.113] (II) NOUVEAU(0): Modeline "1280x1024"x0.0 108.00 1280 1328 1440 1688 1024 1025 1028 1066 +hsync +vsync (64.0 kHz e)
[ 77188.113] (II) NOUVEAU(0): Modeline "1280x960"x0.0 108.00 1280 1376 1488 1800 960 961 964 1000 +hsync +vsync (60.0 kHz e)
[ 77188.275] AUDIT: Mon Nov 16 20:10:39 2015: 5849: client 35 disconnected
