Non-system disk or disk error message
This type of message appears when the computer attempts to boot from a disk on which Windows is not installed, or if the disk is corrupted.

Here are some simple trouble shooting tips you can follow to solve this "Non-system disk or disk error" error message.

1. Remove any removable media from the device, and disconnect any drive that’s connected to the computer through a USB port.

2. Make sure that your computer is booting from your internal hard drive where Windows is installed. Boot your computer into BIOS Setup Utility and from "Boot" tab, make sure the hard disk drive where Windows is installed is the first boot device.

Non-system disk or disk error message CNtNAPL

3. If instruction 1 and 2 doesn't fix the problem and the error still persist, there is a probability that some portion of your hard drive might be corrupt specially the boot sector of your hard drive. Boot you computer with Windows setup media and start the Command Prompt or Recovery Console. Execute following commands one at time.


Code:

Fixboot

Fixmbr


The Fixmbr and Fixboot command is only available for Windows XP and Windows 2000.


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Fix the MBR and boot sector in Windows Vista and later versions of Windows. Execute following commands one at time.




Code:

bootrec /FixMbr

bootrec /FixBoot



4. Remove the installation DVD from the disk tray and restart your computer.


5. If the instruction 3 doesn't fix the problem, then you have to open the casing of your computer and check for the cable connected to your hard drive. The error might be due to a loose connection between your motherboard and your hard drive.

6. If the instruction  5 doesn't fix the problem then your hard drive may have failed. If your hard drive has failed you have to replace your hard drive and you have to clean install windows on your new hard drive.