Well, as the installer is loading, slipstreamed discs don't load smoothly but the original disc does. So it loads each module (Kernel debugger, etc.) right at the beginning of the process, and during that phase the slipstreamed discs seem to spin up, then stop abruptly, then spin up again. This takes 2 or three times longer than the original disc. It usually makes it through the formatting ok. When it copies files, it sometimes claims it can't read them... it choked on 4 or 5 files last time. Some of them were just fonts, but others I could not skip. Once it almost made it to the end, then said something about a corrupt hive. I have not tried checking the CD with CDcheck, but I will do so. This is a problem I have had on several slipstreamed CDs using several different methods, so I don't know how every CD could be bad. I'll check anyway. The service pack and the original disc are both the same language. It seems that many people are able to do this without incident. nLite is pretty foolproof, so I must be doing something wrong... Thanks for your input!