16bit MS-DOS error installing iprep ?

[GRASSASS]

well heres 1 iv not come across yet im getting an error trying to install iprep (or actually running iprep) i get "the NTVDM CPU has encountered an illegal instruction SC:0dff IP:02B2 YADDA YADDA"
ANY WAY,i recently had to replace my mobo and have gone from win7(how easy is it to do on win7?) to xp again to flash a m8s box and cannot run iprep because there is something wrong with ? ms-dos? i reckon somebody here has had this problem (if anywhere) and fixed it so here i am asking for your help once more guys
iv been through the normal process,restore,reinstall,google all that i try does nothing iv done the VDD value thing its just not working ?
it was all fine and i liked win7 but thought i couldnt flash a box on it ? can i ? whats this error is there an easy fix ?
thanks

i was gona post in pc section but its xb related :rolleyes:

WOOHOO im a board warrior thanks

[GRASSASS]

iv just found and tried this "Windows Quick Fix 16 Bit MSDOS System" but that didnt work either ?

ah i just found iprep 12 after a bit of an error its got me a iprepusb up and running i noticed once it had completed that it has a "DOS" in it now, thats instead of dropping in the dos folder eh nice (yes i still use the dos folder-still never used jf all the way through:))
but iv now got a usb to commence the little beauty

but still dont have a clue how to fix that dos thing if any1 does please let me know