Apoligies for beating a dead horse! I have seen this problem everywhere but no working solutions or explanations of the cause. I have spent hours on this problem, and many more hours searching for a solution on the web. There are dozens of instances where others have had the same issue, but no one clear solution. When attempting to slipstream sp2 into a dell oem xp home cd part# 3R350, the installation fails while loading the initial drivers with the error message "the file usbehci.sys is corrputed", and it it not possible to continue. I have tried manual methods of slipstreaming and used nlite as well. I also tried to remove the usb hardware support in nlite. Before I completely give up and go another route, I have decided to register for this forum and submit this post. Other then the desire to create a sanitary install cd out of my old non service packed one, one issue is that my new 500 gig drive is not recognized correctly by an xp cd prior to sp2. Prior cd's see it as a 130gig. I have had bad luck loading operating systems on hard drives that are not seen correctly, corruption, etc. Also I have files on a second partition on my 500 gig drive. This partition is also not seen by my original non sp cd. thanks in advance for any help, R.