I have a emachine computer that I reformatted using the restore disk. the installation did not finish i assume the disk is damaged. so i put in a friends copy of xp and tried to enter my COA. XP would not accept my COA. SO i have been reformatting the computer every month to keep it working. why will it not accept my COA that is located on the back of the computer? Also, at work we was several computers that we though out weekly. could i use the COA off one of those computers? is there a chance that they could find out i use one of the trashed computers coa. they have a company come and dispose of all pcs due to confidentiality and will not let anyone buy them. thanks for you help.