No Bootable Device. Insert boot disk and press any key.

Problem

When turning on your Mac, you get the following message:
“No Bootable Device. Insert boot disk and press any key.”

Cause

This can be caused by a faulty or failed Windows installation or the computer is unable to read from the hard drive which may be faulty.

Solution

I am using a Windows based computer

Repair disk errors using a Recovery Disc.

I am using a Mac

1. Turn on the Mac and hold down the alt key until you get some icons to choose from.
2. Click on Macintosh HD (or whatever you named your hard drive with Mac OS X).
3. It will now boot into Mac OS X. Once you are logged in, click the Apple menu in the top left of the screen.
4. Click System Preferences.
5. Click Startup Disk (found under the System heading).
6. Click on Macintosh HD.
7. Close System Preferences.