This article is from the GNU Chess and XBoard FAQ, by Tim Mann firstname.lastname@example.org with numerous contributions by others.
Try running XBoard again with the "-debug" flag on the command line.
This will print out all the messages received from GNU Chess.
If you see this problem as soon as GNU Chess starts up, most likely GNU
Chess is exiting with an error message. If you see the message "NO
LANGFILE", it means that you did not install GNU Chess correctly, and it
is unable to find the file gnuchess.lang. Make sure that you defined
LIBDIR in the gnuchess Makefile, and that gnuchess.lang is in that
directory. If gnuchess.lang is not there, you probably didn't type "make
install" in the gnuchess src directory; you must do this to install
gnuchess.lang (and the gnuchess book). If you defined LIBDIR to
something that is not an absolute pathname (that is, to something that
does not start with a "/"), GNU Chess will work only if you run it from
the GNU Chess "src" directory where you built it.
If the problem happens while GNU Chess is running, you may have hit a
GNU Chess bug. There used to be a bug that could corrupt the stack and
cause the program to exit, sometimes with a nonsensical message first,
sometimes with no message. It was especially evident on Linux. We
believe this bug is fixed in GNU Chess 4.0.pl77 and later.