Adding IDE CDROM or HD to A1200. Need help

[Thomas]

You can have only two devices on the IDE cable, not three. If the internal HDD is set to master, the external device needs to be slave and vice versa. Cable select does not work. CD drives are only recognised with extra software like IDEfix. 3.5" devices need a seperate power supply, they don't get power through the IDE cable like 2.5" devices do.

[Thomas]

Check Devs/DosDrivers/CD0. It says somewhere Unit=5. Change this to Unit=1. Or install IDEfix again, it creates a proper CD0 automatically.

FindDevice only lists the devices, it does not change anything on the installation. You have to change this manually (as I said, change unit=5 to unit=1).