I’ve just bought a copy of MacOS 8.5. So when install it on my Macintosh LC630’s external hard drive it would not show up in my start up disk control panel. I’ve formatted it, I’ve made sure it could read my LC. It will mount it but won’t start up. I’ve done every thing *Well not every thing* it worked on my mates machine (a nice Powermac G3 minitower with lots and lots of stuff) it just won’t work. Please help!

This is because your computer does not meet the requirements to run MacOS 8.5. It requires a certain computer architecture to run MacOS 8.5. This version of MacOS requires a PowerPC processor to run. Your computer does not have this processor. There is an upgrade kit for your computer but this will not fix your problem. Before buying software always check the label on the box that will tell you if it is compatible with your system.