Hi, Bart. I tried switching the emulator as you suggested. Different behavior, but actually somewhat even worse than before. The Cadd program itself still crashes both itself and dosemu, with the error message athena:jeg> xdosemu & [1] 2404 athena:jeg>ERROR: eVGAEmuFault: unimplemented decode instr at 080b3db7: \ 3b401088 returns to shell; xdosemu window vanishes. The boot.log is not any more informative, but at least both say SOMETHING: ======================= ENTER CPU-EMU =============== ERROR: eVGAEmuFault: unimplemented decode instr at 080b3db7: 3b401088 leavedos(22083|0x5643) called - shutting down leavedos() called from within a signal context! ======================= LEAVE CPU-EMU =============== But this version also crashes both itself and the dos program for the very simple little cadd configuration program, which is entirely text mode and writes a little ~1 kb text configuration file. It dies and says athena:jeg> ERROR: EMU86: error 96 returns to shell, window goes away. This happens at the very end while the file is being written; it gets about a third of the way done and dies--always in the same place (about 5 lines in) in the file. the boot.log says ======================= ENTER CPU-EMU =============== ERROR: EMU86: error 96 leavedos(0|0x0) called - shutting down ======================= LEAVE CPU-EMU =============== So no better off than before. If there is anything I can do, please let me know. thanks much --jim - To unsubscribe from this list: send the line "unsubscribe linux-msdos" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html