Comment 57 for bug 103148

I had this issue when I installed the kde4 package and set kdm to be my default desktop manager, decided I didn't like it, and uninstalled the kde4 package. The next time I booted, I got this error message. I was able to get into gdm by typing startx at the console, and from there I was able to install the kde4 package again, use the prompt it gives you on install to set my default DM to be GDM, and then uninstalled kde4 again. Admittedly, there was probably a more direct way to set my default DM to be gdm, but that was the only way I could figure out how to do it. That fixed the problem. This was on Hardy.