This may not solve your problem, but when I needed to put the default profiles directory on drive D: without using WINNT.sif. I changed to in a file named HIVESFT.inf in the I386 directory. I just have to make sure that partition D: has a filesystem(formatted to fat32 or ntfs) before I start the installation. I haven't made the whole unattended thing work yet, but this part of seems to. Hope this helps, ebaysuks