Using SysPrep "wizard". Started on a brand new ACER notebook by doing a CTRL, SHIFT, F3. I verified acceptance of some RAM I had installed, then tried to do a RESEAL. An error box popped up -- "An error occurred while trying to update your registry. Unable to continue". I tried it multiple times with different options on/off, i.e. "Don't reset grace period", "Don't regenerate security identifiers". I tried the FACTORY, AUDIT, and RESEAL buttons -- all with the same error message. I called ACER support. They had me power down and the back up with the power button. The system resumed with the SysPrep wizard box on the desktop. Acer told me that they do not support SysPrep - "Call Microsoft". I searched the Net and EE for detailed documantation for using SysPrep with XP Pro. I did not find any documentation references.
I have used this method multiple times before without problems on new machines and on OS re-installs to pre-install applications and/or verify drivers.