I don't think that is the issue. The "official" maximum OS on my Powerbook 2400c and my PowerMac 6500 are both 9.1. However 9.2.2 installed via OS9 Helper works great on both of those machines. In this case the Duo is not even recognizing the hard drive during startup. I can hear the HD spin up briefly and then immediately the blinking disc icon comes up. I suspect the 2400 may require a unique HD driver, because when I put a new HD in the 2400 it had to be reformatted by the 2400 in order to work. I could reformat this HD in the 2300, but I am reluctant to do so. Also, it may not be possible, as when I use Disk Tools on the floppy - it cannot 'see' the internal 1.13G HD. Thanks, joe To: "A place to discuss Apple's sub-portable computers." <duolist at listserver.themacintoshguy.com> Message-ID: <738908.51633.qm at web50903.mail.re2.yahoo.com> Content-Type: text/plain; charset="iso-8859-1" I researched and found that the 2300c can only run OS 9.1 or lower. That may be your problem. Here is the website I found the information at: http://www.danpalka.net/powerbookduo/profiles/duo2300c.html Art in Silicon Valley