DC is a very good program but I just started running XP conservatively (run as non-admin user, DEP set /optout) and came across a glitch - the O/S Data Execution Prevention dialog closed the program. When DC is added to the DEP exception list, it works normally.
System - XP Home SP2 fully patched, AMD X2 BE-2300 processor
I had the same problem with windows server 2003 (I know it is not "officially" compatible"..). When I read your message I realized that this could be the problem and now it works. (I have to exclude Dup.Cleaner from DEP). Thanks