if you encounter a big red ERROR message on downgrading to XP on Asus laptop, it’s a wrong setting in the BIOS Sata operation mode. It’s not your faulty lap (or at least, not only :) You can try following the advice here (in italian): http://www.m-link.it/m-link_news/Errore_del_cd_recovery_Asus_nel_downgrade_da_Vista_Business_a_XP_Professional.asp Thanks m-link