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Am trying desperately to boot ubuntu 12.10 off a livecd. I get to the startup screen and choose the "Try" option. It just goes to a black screen with a flashing cursor. I have tried "nomodeset" option but it seems to just reboot and not save the setting on the next reboot. What am I doing wrong ? Any help would be much appreciated as I am in a bit of a data crisis. Need to pull critical files off a RAID 0 so I need to boot off cd to access the RAID. Thanks