can't run X - permission denied

[Lars Jensen <jensen@scsr.nevada.edu>]

Only root can run X windows and certain other programs on my machine.
I'm not sure whether I inadvertently changed something. This wasn't a
problem before. Other programs behave the same way, for example if I use
"which" as a user, the system responds:

/usr/bin/which: /dev/null: Permission denied
/usr/bin/which: /dev/null: Permission denied

I checked the permissions and thy are set to 755, i.e world executable
and readable.

Any ideas how what this could be?

Thanks,
Lars.

--
Lars Jensen, Truckee Meadows Community College, Reno NV 89512-3999.
Tel: 775.673.7113 E-mail: jensen@scsr.nevada.edu