No explanation given. I bought this because the hard drive on my G4 crashed. I thought that I could get an updated tablet later for the internet, but just needed something right away for , email and publishing and whatever web sites I still could open. I gave the shop owner my OSX Leopard 5 Install DVD to download for me into the G5, but he, I found out later, installed a remote version 4.11. I am still waiting for an explanation from him. On the G4 I was running 5.8 but can't remember how I got up to 5.8. I think that a lot of little problems that I am experiencing could be corrected with 5.8. Anyone know what needs to be done to correct?