This happened to me when I tried to use any location other than %systemroot%\system32\sysprep\ as the location of the unattend.xml file and I don’t use the full path when calling sysprep from the comman line. usually my sysprep call looks like
[CODE]C:\Windows>%systemroot%\system32\sysprep\sysprep.exe /generalize /oobe /shutdown /unattend:%systemroot%\system32\sysprep\unattend.xml[/CODE]
J