I purchased a new computer and ordered it w/ Works thinking I could use my Office 2007 Upgrade CD I used on my old computer (to upgrade from Office 2003). Apparantly that won't work?? It says I don't have a valid Office copy on the new computer and it doesn't recognize the Works either. I thought you could install on 3 computers?? My old computer had OEM installed software which was Office 97 upgraded to 2003, to 2007. Do I need to buy a full copy for the new computer??? Thanks in advance.