thx Tripredacus what i meant are in question 1 & 2 are the same...it is not about BartPE...most of the files in VISTA PE are put in vistape.wim if you view the ISO, but if you run the VISTA PE it will loads the vistape.wim contents (%imageroot%\Program Files\, %imageroot%\Program Data\, %imageroot%\Windows\) into Boot (X:) drive...since i combined both OS (VISTA PE & BartPE's XP) into one ISO, i want to share it to my BartPE's XP, so both OS will use the same stuff and i want to know the method in VISTA PE when it is boot and mount vistape.wim so i can experiment the same inside BartPE's XP... question 3, understood...