Before I go any further, bear with me as I am not overly technically minded, although I do know my way around this machine. I used nlite 1.4.5.1 in XP to slipstream SP3 with my XP Pro SP2 disk (x86) and to test it I went through an installation of XP on a spare partition and I got the errors mentioned in my header quite late on in the process. However, when I pointed it to the appropriate area on the CD (napprov_mo and rsop_mo if I recall correctly) it accepted that and completed the installation without further objections. What surprised me was that it appeared that it was already looking at that area in i386 anyway, but something caused those pop-ups. Anyway, the installed product worked fine. I've since formatted that partition and installed a 2nd edition of my Vista for testing purposes. Does the final version of nlite work better in this regard? If so I'll re-do the slipstream.