By Lily / Last update July 7, 2021

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Overview of “Error loading operating system”

Sometimes, when you try to boot your Windows PC, you may come across an error message: “Error loading operating system”. It is found on different brands of computers. Some users encounter Lenovo “Error loading operating system” while some users are troubled by Dell laptop “Error loading operating system”. And there are users who receive the error message when they boot their computer from a Windows recovery USB drive.

The startup issue generally occurs after the fresh installation of the Windows operating system, sudden power failure, system crash, or system restart. Here is a real case:

“I have a problem that I have found in other posts, Error loading operating system in Windows 10! The system updated and restarted overnight and now I am stuck with this. I forced shutdown and restart the computer, and it is still on the error screen. I can access the hard drive files via CMD from the recovery menu! Can anyone help?”

Error Loading Operating System

What situations may lead to this error?

There are five major causes for “Error loading operating system” in Windows 10/8/7:

1. The computer’s BIOS does not support the hard drive.

2. Multiple hard drives have been connected to your computer and you have set a wrong drive to boot from.

3. The hard drive’s system partition is damaged due to sudden power cuts, virus infection, or disk write error.

4. The system files used to load the operating system are missing or damaged.

5. Master Boot Record (MBR) is damaged.

How to fix "Error loading operating system" in Windows 10?

For cause 1, you may update your computer’s BIOS to fix the boot issue. For other causes, please learn the corresponding solutions below.

Method 1. Set the right boot device

Step 1. Restart your computer and continuously press a specific key to get into BIOS. The key to open BIOS can be listed on the first screen that appears, before the Windows logo shows up. It is likely to be Esc, Del, F2, F8, F10 or F12.

Step 2. Go to the Boot tab and use the keys prompted on the screen to set a right device to boot from. If you are confronted with “Error loading operating system” from a USB drive, make sure “Removable Device” is at the top of the list.

Change Boot Order

Step 3. Press F10 to save changes and restart your computer.

Method 2. Fix hard disk errors via Windows CHKDSK tool

CHKDSK is a Windows built-in tool to gauge the general health of your hard disk. It can check hard drive for errors and fix bad sectors and errors if any.

Step 1. Insert the Windows 10 installation CD/DVD to your computer and boot from it.

Step 2. Choose your keyboard layout.

Step 3. Click Repair your computer in the lower left corner.

Step 4. Select Troubleshoot -> Advanced options -> Command Prompt.

Step 5. In Command Prompt, type chkdsk c: /r and hit Enter to fix errors on C drive. You may replace C: with the letter of the drive where Windows is installed according to your situation.


Method 3. Perform Startup Repair

Startup Repair is a useful tool to fix boot issues caused by missing or damaged system files.

Step 1. Boot your computer from the Windows 10 installation media and go to Repair your computer as you do in Method 2.

Step 2. Select Troubleshoot ->Advanced options ->Startup Repair in sequence. Startup Repair will scan your computer for problems and fix them automatically. The computer may restart several times during the process.

Startup Repair

Method 4. Restore the MBR information of the hard disk

Step 1. Boot your computer from the Windows 10 installation media and open Command Prompt as mentioned in Method 2.

Step 2. When the Command Prompt loads, type the following four commands and press Enter after each command to fix MBR in Windows 10 and rebuild BCD.

  • bootrec /FixMbr

  • bootrec /FixBoot

  • bootrec /ScanOs

  • bootrec /RebuildBcd


Rebuild MBR


Step 3. Type exit and press Enter. Remove the CD/DVD and restart your computer.

Further reading: backup OS as a last resort

As you know, system issues happen from time to time. And some system issues can’t be fixed by regular solutions. You have to perform system restore to bring your computer back to work. Therefore, it’s important for you to backup your computer when it’s in good condition.

AOMEI Backupper Standard is an overall backup and restore tool which supports system backup, partition backup, disk backup, and file backup. It is free and easy to use. You can schedule an automatic backup for your compute OS so as to keep your system image up to date. With its clean and tidy interface, all you need to do are a few clicks.

System Backup

Tips: To boot your computer in case of boot failure, you can make a bootable media via AOMEI Backupper. If you haven’t made a bootable drive before boot errors occur, you may create one on another working machine, and then boot your computer from it.

★ Advanced way to backup OS:

Instead of creating system image backup and bootable media one by one, you can choose to use one key recovery software AOMEI OneKey Recovery to achieve the same effect by creating them simultaneously. It allows you to boot computer using F11 or A key when it fails, and you can access this software to factory reset your computer, for example, Lenovo desktop factory reset, or just restore to the backup state.

OKR Backup


This page offers you four effective methods to fix “Error loading operating system” in Windows 10. To better protect your computer system, you may backup your computer with AOMEI Backupper. Actually, it is also a free SSD migration tool that can help you upgrade HDD to SSD effortlessly. Just give it a shot!