[Tommy Atkins]

I've run MOHAA under Mac OS9.2.2, but when I try to install (from original genuine disks) onto my OSX G4 I get the message 'Please insert the CD "Medal of Honor CD1" into your CD-ROM drive or press quit', even though CD1 is in the drive and clearly mounted on the desktop.
My son tried earlier (without success) to install MOHAA onto the same drive from a cloned disk - are there invisible prefs lurking somewhere in the system which prevents the real version from being recognised? If so, how do I uninstall them?