You are obviously not talking about a standard Windows XP setup, so no one can answer your question unless they know of an application that (you don't name) allows installing windows by using/starting a single 5Gig exe file. you don't know my question... i say can windows Xp setup work in UDF? that 5Gig file is a setup file that i make and some programs is in it that should be in that disk... just say windows xp setup work in UDF partition??? if not work how can customize it to work in UDF???