My daughter's MacBook got the dreaded blinking folder/question mark. Took it to the Genius Bar and was tested & told the HD was dead. They'd replace it for $170 with a 160Gig drive. I brought it home, ordered a 500Gig Seagate drive for $65 (after much research). Installed it easily enough, turned on MacBook and got the dreaded blinking folder/question mark yet again. Tried the following: 1) Starting with orig OSX disk holding down C - blinking ? and kick out of CD after a few minutes; 2) Zapping PRAM; 3) Starting with Diskwarrior & holding C (also tried holding down OPT) 4) Tried holding down OPT/CMD/O/F 5) Used TechTools - holding down OPT All results the same - the blinking ? The CD This is pretty upsetting to me since I cannot afford a laptop for my daughter who uses it extensively for college. Any ideas, recommendations or suggestions? I'm really desperate now. And terribly sad.