My hard drive was dying on my macbook, so I ordered a Hitachi upgrade from here, which came today. I installed it and turned on the computer,but it is just showing a file symbol with a question mark- it can't read the drive.

I tried inserting the OS disc, which worked, until it asked what drive to install the OS on, then it doesn't show the drive as an option.

I also plugged in my external drive with my whole Time Machine backup, and then turned on the computer, holding down the option key, but it just brought up a white screeen.

Anyone know why? If I got a defective drive, I'm going to freak a little. I have to teach a summer session soon and need to get things back up and running ASAP.

Thanks, Joy