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When I turn on iMac (iMac Intel 21.5" EMC 2428, Model A1311 / Mid 2011)
I get the chime and after some time, a blinking question mark inside a folder icon appears.
I have tried all combination keys on mac wireless keyboard and Windows USB Keyboard but nothing worked.
Then I replaced hard drive for brand new SSD but that didn't change anything.
What else I have tried:
1) All combination keys I could think of. On original mac wireless keyboard and Windows USB keyboard.
D, N, T, Option, Command + R, Option + Command + P + R, Shift, Command + S, Command + V
Whatever combination I use, doesn't make any impact on the boot process and a question mark appears after while.
2) I plug USB Stick with a bootable system and also System on CD but none of the combination keys worked. I'm unable to eject CD using the Eject button on the keyboard. I can only eject using the mouse while starting.
3) I have replaced batteries on the keyboard and when I turn on with side power button I can see a green LED briefly turn on. Caps lock LED doesn't work but I don't remember this working ever.
4) I have removed all but one RAM carrier.
I spent the last few days researching the problem but all point to faulty HDD which I already replaced. What could be a problem? Anything else I could try?