I had bought a new copy of office 2007 which i was trying to upgraded on a Windows XP service pack 2 system that also had office 2003 pre-installed. But when the installation started i got an error message saying that windows installer service cannot update one or more protected windows and office 2007 rolled back installation. After that when i tried to open office 2003, it was not working, so i completely uninstalled it inorder to fix the mapi32.dll error that everyone gets normally and it worked again. After that i uninstalled the office 2003 completely in order to install the office 2007 but it didnt work either. I was getting the same error even after trying to install the new version numerous times. So, can anyone tell me how do i resolve this problem?