Carl, Thank you for that XPL code. I�ve managed to sort out my STARTUP.INT to the point where the only error message is a presumably spurious �vDosPlus only� that flashes by as it loads. If you have a copy of U2 that would include debugging routines, I�ll be glad to test it out. Meanwhile, thanks to your make-it-portable code, I have a one-directory version almost ready, and will finish a DOSBox-X version afterwards.