I tried to instal Ubuntu on an external drive using my macbook. I didn't follow any guides or anything. Now not only does my computer not recognize the external drive to boot from it, it won't recognize any drive to boot from including OSX. All I get when I boot is a flashing folder with a question mark on it. I read that I could make some cd with rEFIt or something on it and that would find the availible drives to boot from but when I made a cd it didn't do anything at all. Please Help! I need my computer for school and can't afford to get it fixed. Hopefully everything is still on the drive... Sorry for this being so long but I don't know what to do. Thanks a bunch.