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I just replaced a Samsung 500g hd with a WD Caviar 2tb hd in my new iMac 21.5 (iMac 11,2) and when it boots, I get a flashing question mark. Do I need a Samsung hd instead of an WD? I thought Wds were compatible.
You need to boot from your system installation disk. Insert disk and hold down the “C” key while starting up. Go to the second page pull down menu to Utilities, Disk Utility and format the drive. Give it one partition. Now go ahead and install a system. iMac Intel 21.5" EMC 2389 Hard Drive Replacement
