Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_2_5 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8E128 Safari/6533.18.5) I recently installed Ubuntu 10.10 via .iso onto a CDR. I then shut down Ubuntu and the disk came out. I took it out and want to switch back to OSX. All I get on startup is a flashing Question Mark Folder. I've tried all the bootup combinations, none seem to work. Anyone care to help?