gdm and xdm just stopped working

After running dselect this morning, I noticed that gdm would fail to start the X server. So I installed xdm instead, and it has the same problem. xinit and startx still work. --begin /var/log/xdm.log-- X: user not authorized to run the X server, aborting. xdm error (pid 756):

gdm and xdm just stopped working

After running dselect this morning, I noticed that gdm would fail to start the X server. So I installed xdm instead, and it has the same problem. xinit and startx still work. --begin /var/log/xdm.log-- X: user not authorized to run the X server, aborting. xdm error (pid 756):