Encountering the “Error Loading Operating System” in Windows 11 or 10 can be a panic-inducing situation. Rest assured, your important files and crashed OS are safe. There are several crucial ways to troubleshoot the “Error Loading Operating System” on Acer, Lenovo, Asus, Dell, and other PCs. Here in this article, we will guide you step by step to fix this boot error.

At times, attempting to boot from a USB device can lead to the occurrence of the above error. This startup issue can be triggered by various reasons.

Cause:

The above error is a kind of Boot failure error that occurs when you attempt to boot your computer. On a blue screen or black screen, you get welcomed with the error message “Error Loading Operating System”.

1. Invalid Boot Device Selection – This issue often arises when you have multiple SSDs/HDDs installed on your computer, and the BIOS is set to boot from a non-Windows drive.
2. Corrupted Master Boot Record – The Master Boot Record (MBR) file is essential for Windows OS, as it contains all the necessary information required during boot-up. If this file becomes corrupted, Windows won’t be able to read it, leading to the “Error Loading Operating System” message.
3. Bad Sector in Storage Device – Bad sectors on your storage device can also prevent Windows OS from loading properly during startup.
4. Incompatible Windows Updates – Installing incompatible Windows updates can cause the operating system to crash, resulting in an error message.
5. Outdated or Misconfigured BIOS – If your BIOS is outdated or misconfigured, it can hinder the proper booting of your computer.
6. Windows Drive is Full – If your Windows partition drive is full, there won’t be enough space to store necessary startup information and log files, leading to Windows startup errors.
7. Windows Partition is Damaged – A damaged Windows partition can also be a significant reason for encountering the “Error Loading Operating System” on Windows 11.
8. Sudden Power Cut – A sudden power interruption during update installations or driver installations can cause boot issues and trigger the above error.
9. Hardware malfunctioning – It may be possible that your HDD or SSD is malfunctioning or reaching the end of life. Due to a dead storage device, BIOS is not detecting the boot device.

As you can see, there are various reasons that can cause trouble during Windows 11 startup. However, there’s no need to worry. Simply follow the solutions provided and apply them step by step to repair any Windows 11 startup problems you encounter.

Solution 1: Select the correct boot device in BIOS.

To resolve the issue, it’s essential to check which storage device is selected as the primary boot device in BIOS. Ensure that your storage device containing the Windows partition is set as the primary boot device. If another device is currently selected, you can change it by following these steps:

Solution 2: Repair the Corrupted MBR file

Corruption in the Master Boot Record can lead to the “Error loading operating system” message. To repair the MBR, you can use the built-in Windows 11 recovery tools. Follow these steps:

If, for some reason, the MBR recovery command fails to execute or does not fix the MBR corruption, you can utilize EaseUS Partition Manager to repair the corrupted MBR file. This tool not only resolves MBR corruption but also enables you to repair a crashed OS and boot your computer effortlessly.

Repair MBR using EaseUS

Step 1: Create Bootable USB drive using EaseUS. Launch EaseUS Partition Master, and click “Bootable Media” on the toolbar. Select “Create bootable media”.

Step 2: Boot your PC using Bootable USB Drive.

Step 3: Click “Toolkit” and choose “Rebuild MBR”.

Solution 3: Fix HDDs/SSDs bad sector, system file corruption and repair Windows image

Fixing issues related to bad sectors in the Windows partition, missing system files, and corrupted Windows image files is another crucial aspect of resolving the “Error Loading Operating System” on Windows 11, 10, 8, & 7. These factors often play a significant role in causing boot errors. To resolve the problem, it is essential to address all these areas. The good news is that you can fix these problems using the built-in Windows commands.

Solution 4: Use Startup Repair

Startup repair is an effective option for fixing the “Error loading operating system” issue on Windows computers. To perform the startup repair, you will need a WinPE Bootable USB drive. If you don’t have a WinPE Bootable USB drive, you can create one using the following methods.

Create WinPE Bootable Drive using EaseUS Partition Master

Step 1: Insert 8GB+ USB flash drive to computer.

Step 2: Launch EaseUS Partition Master and go to Toolkit → Win 7/8/10/11 ISO.

Step 3: Browser your ISO file and click Next.

Step 4: Select your USB drive and click on Start button to create Bootable Windows 11/10/8/7 and Windows server USB drive.

How to Perform Startup Repair

To perform a startup repair, you are required to insert a bootable USB drive into your computer and then change the primary boot device in BIOS. After booting your computer from the USB drive, open the Advanced Startup options and proceed with the startup repair.

Startup Repair - Step by Step

Step 1: Boot your PC using the Windows Installation media. It will open Windows Installation Wizard. Click Next.

Step 2: Select Repair your computer.

Step 3: It will open the Advanced Startup Option or Windows Recovery Environment. Click on the Troubleshoot.

Step 4: It will open the Advanced startup menu. Go to the Troubleshoot ➜ Advanced options ➜ Startup Repair.

Step 5: Select OS.

Step 6: Wait until it diagnoses and repairs your PC.

Solution 5: Fix Windows Partition drive issues.

Fixing any issues in the Windows Partition Drive is equally important. You can manage the Windows partition by following these steps:

Manage Driver Partition using EaseUS Partition Master

Resize/Move: This powerful feature allows you to adjust the space of a selected disk partition, enabling easy resizing or moving of partitions to suit your needs.

Clone: With this handy feature, you can create a clone of your first hard drive onto a secondary hard drive. This comes in extremely handy if your primary hard drive is malfunctioning and you need to replace it with a new one. The clone process transfers all data seamlessly to the secondary hard drive.

Delete: Unwanted disk partitions can be swiftly removed using this feature, freeing up space and converting them into unallocated space.

Format: When you need to format a partition, this feature ensures a straightforward and efficient process.

Allocate Space: Easily settle one drive’s space to another using this feature, making it simple to manage your disk partitions.

Migrate OS: Say goodbye to the hassle of reinstalling Windows when you want to change the installation drive. This feature allows you to migrate the Windows installation drive seamlessly.

Convert GPT/MBR/NTFS/FAT32: Changing the drive system type is a breeze with this feature, all without the risk of data loss.

More to Explore: In addition to the above features, the WinPE Partition Master Environment offers even more options to explore and manage your drives.

Solution 6: Replace the HDD/SSD

It is possible that the HDD/SSD installed on your computer is malfunctioning and not working properly. This could be due to damage or reaching the end of its lifespan. Try re-inserting the storage device, and if the issue persists, consider replacing it.

Before replacing the hard drive or solid-state drive, it is crucial to back up all your stored files, documents, emails, and other types of data using the EaseUS Data Recovery Wizard. This powerful tool can also recover deleted data, including photos, videos, documents, PDFs, MS Office files, emails, and more, and repair them during the recovery process.

Solution 6: Re-install Windows 11/10 OS

If you are still encountering the same “Error Loading Operating System” problem after trying all possible solutions, the last resort is to re-install the Windows 11/10 OS and perform a fresh start of your operating system. Although this process can be cumbersome, complex, and time-consuming, it is the ultimate option to resolve your problem effectively.

Step-by-step Guide to Installing Windows from a Bootable USB Drive

Step 1: Boot your PC using the Windows bootable USB drive.

Step 2: When prompted with the message Press any key to boot from CD or DVD… simply press Enter.

Step 3: Click on the “Install now” button.

Step 4: In the next window, choose your Language, time, currency format, and keyboard layout, then click Next.

Step 5: Enter your product key. If you don’t have one or prefer to do it later, click on the I don’t have a product key option.

Step 6: Select your Windows edition and click Next.

Step 7: Accept the License and Terms.

Step 8: If you want a fresh installation of Windows 10/11, choose the Custom Install Windows option.

Step 9: Create your partition drive by clicking on the New button. If you already have a partition drive, select it and choose to format it. Once formatted, select the partition and click Next.

Step 10: The setup will start installing Windows on your selected partition drive. Please wait until the process is finished.

Step 11: Follow the installation instructions, select appropriate options to customize your PC, and you’re done!

Summary:

To fix the “Error Loading Operating System” on Windows 11/10/8, start by selecting the correct boot device in BIOS, repairing the MBR file, fixing disk errors, and performing startup repair. If the issue persists, the last resort is to re-install the Windows OS.