As the size of hard drives increase, more people are using partitions to separate and store groups of files. XP uses the C:\Program Files directory as the default base directory into which new programs are installed. However, you can change the default installation drive and/ or directory by using a Registry hack. Go to :- - Start > Run - Type “regedit” (without “” NOOBS!) - Go to this directory… HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion - Look for the value named ProgramFilesDir. by default,this value will be C:\Program Files. Edit the value to any valid drive or folder and XP will use that new location as the default installation directory for new programs.