Crashing excel on exit
 

I'm using a workspace in excel 2003 consisting of one xls file having three
diagrams and one xml file storing the data for each of these diagrams. I've
diveded it in this way since I have to modify the data using java and Java
can't read xls files. I've created links between the xls and the xml file and
grouped them together in the xlw file so that updating of the diagrams is
done once the files are opened without any warning that the source file isn't
open and such.

My problem is that excel crashes when I exit the program is the files are
opened, not always but most of the time. I have tried different approches and
seen that excel doesn't crash if I first close the xls file and then the xml
file, if I do it the other way around it always crashes.

Is there somebody who has a clue about why this happens and what I can do to
prevent it? I don't want to deliver a program that crashes excel when they
try to use the file I modify.