Help - X does not start. Error messages cryptic

Upon each following reboot and attempt to boot X:

#startx
execve failed for /etc/X11/X (errno 2)
_X11TransSocketUNIXConnect: Can't connect: errno = 111
giving up
xinit: Connection refused (errno 111): unable to connecct to X server
xinit: No such process (errno 3): Server error.

What does this mean, and what can I do to fix it?