HELP! Osbourne drives

I played with the Osbourne Executive yesterday. I can't get it to boot. All it says is "boot error". It says the same thing with no disks in it, MS DOS disks in it and with the door open so the message doesn't tell me anything. I tried swapping drives, reseating ICs and cables and everything that I could think of. It booted once and I did DIR on both drives with no problems, it almost booted several times but filled the screeen with garbage and locked up. I tried disks from three different sets including a set of new copies from Don Maslin so I'm sure the the disks aren't the problem. Any ideas? Does anyone know if DS drives can be used in these? The drives in it are ALPS SS DD. I took the drives out and checked them, the heads and drives are clean and the speed is right. I don't think there is anything wrong with them. Several people have posted messages here in the past about problems with Osbournes that wouldn't boot. Did you ever get them working? What have you found wrong with them? Joe