Windows 10 users experience a variety of error codes, glitches, and problems on the operating system. But out of all the errors, the most terrible or dreaded error to show up on the screen is ‘Operating System not Found.’ It is a dreadful sight to see, but the bitter truth is that it is most likely to happen at some point. Despite this error, your data on the system remains safe, and you can still get access to your most important files. If you see this error code on your PC screen, use the following guide to solve this problem:
Check the Basic Input/Output System (BIOS)
In the BIOS, you need to make sure that your machine recognizes your hard drive, and the drive on which Windows OS is installed is programmed as the Preferred Boot Drive. The entering procedure in the BIOS varies from manufacturer to manufacturer. But the most common keys that you’ll need are to press one of the Function keys, Escape, or Delete key. You will find a message appearing on your screen, advising you about the boot process’s correct access key.
Please note that the BIOS menu also varies from device to device. Using your keyboard, you need to locate the Boot tab along the top of the screen. Within the Boot tab, use the following steps:
- Highlight the Hard Drive and press the Enter key. Ensure that the Hard Drive is listed above USB Storage, Removable Devices, CD/DVD\BD-ROM, and Network Boot.
- Adjust the order using the (+) plus and (–) minus keys.
If you don’t find the hard drive listed, then try to reset the BIOS to default. The procedure to reset the BIOS starts at the bottom of the BIOS menu. In the menu, you will find a key for Setup Defaults or Reset BIOS. Press either of the Function keys (that works for your PC) and confirm your decision when prompted. To save the settings, restart your system. Now you are ready to move onto the next step.
Fix the Boot Records
Typically, Windows relies on the Master Boot Record (MBR), DOS Boot Record (DBR), and the Boot Configuration Database (BCD) to boot your PC or laptop. If either of these three records gets damaged or corrupted, then the user encounters the “Operating system not found” error message on their system. Fortunately, you can fix them using a removable Windows installation drive. We would recommend you to use Windows Media Creation Tool for this procedure. Depending on the system you use, you’ll have to use a single key or change the boot order from the BIOS menu during the process. Follow these steps to continue:
- You’ll find a Windows Setup screen where you have to enter your preferred language, keyboard, and time format.
- Then, click on Next and select Repair Your Computer.
- Go to Troubleshoot and click on the Advanced options.
- Select Command Prompt and enter the following commands:
Don’t forget to hit the Enter key after each command line, and each one of these will take a few minutes to complete. Once the procedure completes, restart your PC and check if it boots successfully.
Enable or Disable UEFI Secure Boot
Every Windows system has a UEFI firmware and Secure Boot enabled, but it fails to work properly in many cases. And the reason for its failure could be that your Windows 10 system is running on an MBR disk. It will disable your device from booting in UEFI mode. This is why it is crucial to enable or disable the UEFI Secure Boot and check if it is good enough to make a difference. You have to make the adjustments in the BIOS menu’s Security tab. Then, click on the Secure Boot option.
Activate the Windows Partition
One of the reasons you see the ‘Operating System not Found’ message could be that the Windows partition has disabled. But, using Windows’ native diskpart tool, you can fix the issue. To go through the procedure, you’ll need the Windows installation media USB, and then follow the steps given below:
- Turn on your PC and boot from the tool.
- Then, enter your language preferences, etc., click on Next.
- Select Repair Your Computer, and go to Troubleshoot. Click on Advanced Options and select Command Prompt.
- In Command Prompt, type “diskpart” and hit the Enter key.
- Insert “list disk” and press the Enter key. This will bring you a list of all the disks attached to your system. Note down the disk number you need.
- Then, type select disk [number]. Replacing [number] with the disk number mentioned earlier, and then, hit the Enter key again.
- Now type list volume and press Enter to see all the partitions on the disk you selected.
- Find out the partition Windows is installed on and again note down the number.
- Then, type select volume [number], again replace [number] with the number you noted.
- Insert “active” and press the Enter key. Restart your desktop to check the final results.
Despite using all the techniques mentioned above, if you continue to see the ‘Operating System not Found’ message, you must visit an expert or a computer repair shop.
Graccey Leio is a self-professed security specialist; she has been manufacture the people aware of the security threats. Her obsession is to write about Cybersecurity, cryptography, malware, societal engineering, internet and new media. She writes for McAfee security products at mcafee.com/activate.