There are several common reasons for Non System Disk or Disk error immediately after Windows boots up:

->Boot your PC from a media without boot files.

->A loose or faulty SATA or IDE cable on your HDD.

->Your BIOS settings are not correct.

->The boot configuration (Mater Boot Record, MBR; or Boot Configuration Data, BCD) is corrupted in your hard drive.

Well, you do not have to look up through the list and search for what is SATA. This problem can be resolved and Non System Disk or Disk error could be rooted out. Here are some step-by-step methods to fix it.

Solution 1 Remove all the non-bootable media

Make sure you have disconnected all the media that computer cannot boot from, including CDs/DVDs, USB flash drives, and floppy disks. Then restart your computer and see if you are still facing the problem. If the error persists, try Solution 2.

Solution 2 Check your HDD’s IDE or SATA cable

A loose IDE or SATA cable could cause the Non System Disk or Disk error. An IDE or SATA cable is to detect, recognize and read from storage devices (like hard drives) and connect it to a computer's motherboard. Thus, a loose IDE or SATA cable will cause the hard drive cannot be detected by Windows, which may lead to the non-system disk or disk error in Windows XP/7/10.

Make sure you have connected hard drive via corresponding ports and restart your computer, or check the IDE or SATA cable on another computer to see if the cable is damaged. Otherwise, try the next solution.

Solution 3 Set the right media in BIOS settings

Make sure the media you put in has been set as the first boot device.

1. Restart your computer and then press the key to access your BIOS (This key varies from one motherboard manufacturer to the other and you could get it on Google “the key to access + ‘your computer brand and system version’”).

2. Then follow the description to select the boot order, then set the media you want to boot as the first boot device.

3. Save the change, exit the BIOS and restart the computer.

Solution 4 Repair corrupted boot configuration

The corrupted boot sector, MBR or BCD could touch off the Non system disk error. Thus, you could try to fix them with Windows installation disc or Windows system repair disc.

1. Insert the Windows installation disc into your computer.

2. Boot into Windows system recovery options, select Troubleshoot > Advanced options > Command Prompt.

3. Then use the following commands to fix non system disk error or disk error in Windows XP/7/10. Press Enter after typing in each one.

bootrec /scanos

bootrec /fixmbr

bootrec /fixboot

bootrec /rebuildbcd

Bootrec Command

4. Remove the installation disc, restart the computer and see if the problem has been resolved.


Another healthy computer without boot problems and a CD/DVD disc/USB drive is required by both bootable software in order to create a bootable storage media. It's necessary to recover data from a computer or hard drive that won't boot, and manage partitions such as partition, format or wipe partition without OS as well as fix hard drive corruption, bad sectors and rebuild MBR. To restore a system recovery data:

1. Open Neptune SystemCare Ultimate, on the top of the interface, you can see a list of buttons.

2. The second button is for creating a restore point. Click on it and Create a system restore point. You can save the file to an external storage drive.

3. The third one is for recovering from the restored version. You can click on it and choose the version/time you want to recover.