New to this group and only used nlite on about 5 occasions previously. I purchased an OEM XP SP2 package from my local computer shop last week. It looks genuine etc, and was sealed. Product key sticker attached. (Yes it did come with hardware too) I needed to slipstream some nvidia raid drivers, so also included SP3 within nlite. Installed with one error on final re-start. C: WAP.EXE. Error only happened once. Come to Windows update, and Validation fails! Tried the original shop supplied CD, on a different machine that did not require the nvidia drivers. No WAP.exe error. Added SP3 post install. Windows updates no problems. Validation not requested, so presumably OK? Original slipstream was done on Vista, but found that there may be issues. Did a second slipstream using XP. Same result! WAP.exe error, and Failed Validation. Now have I bought a pup, in which case I need to know soon so I can go back to the vendor. Or is this an nlite issue? Tried to find somewhere to check the validity of the key on the sticker that came with the CD package, but no joy. Can / should / how contact Microsoft to check? Advice appreciated. Rgds.