Quite a few Windows users found that after they reset or refreshed their Windows 10 computer, it froze in the middle of the process and they forced it to reboot, they were greeted by a blue screen that displayed an error message stating “An operating system wasn’t found. Try disconnecting any drives that don’t contain an operating system. Press ctrl+alt+del to restart.” This is quite shocking as resetting or refreshing a Windows 10 computer does not delete its Operating System, which means that this blue screen should not be displayed at all. In such cases, the computer keeps displaying this blue screen regardless of how many times the user reboots. Many users have also experiencing this same issue after downloading and installing updates for their Windows 10 computer.
The most probable culprit behind this problem is the corruption of system files critical to the proper functioning of Windows. If anything damages your computer’s system files, you may find yourself looking at a blue screen that says your computer has not Operating System whatsoever after you reboot. The following are the two methods that you can use to fix this problem:
Method 1: Try performing a factory reset on your computer
Most computers come with a Recovery partition on their hard drives out of the box – this is a factory-fitted hard drive partition that contains all the data you could possibly need to reset your computer to its factory condition without requiring any additional material such as a recovery disk. Factory resetting your computer has good chances of being able to get rid of the blue screen that says your computer doesn’t have an Operating System. However, it should be noted that factory resetting your computer will delete all of the data stored on your computer’s C drive and that you can only factory reset your computer if you haven’t already deleted its Recovery partition.
The process for factory resetting a computer which you cannot logon to using its Recovery partition varies from one computer to the other, so you might have to do some research on how your specific brand and model of computer can be factory reset. For example, if you want to factory reset an ASUS computer using its Recovery partition, you need to:
Turn the computer off.
Power the computer on.
Repeatedly press F9 as soon as the computer starts booting up.
Press Enter to select the Windows Setup (EMS Enabled)
Follow the onscreen instructions and click on Next in the two windows that follow.
Select the Recover Windows to first partition only option and click on Next. Choosing this option will ensure that only drive C of your computer is formatted and the data on all the other drives is left untouched.
Follow the onscreen instructions to go through with the factory reset process.
Method 2: Perform a clean install of Windows 10
If factory resetting your computer doesn’t work or you can’t factory reset your computer using its Recovery partition for some reason, your only remaining option is to perform a clean install of Windows 10. You should understand that a clean installation of Windows 10 on your computer will get rid of all the applications, data and settings on your computer, but you should not have a problem with that in this case as the alternative is to have a computer that doesn’t have an Operating System on it. To perform a clean install of Windows 10, you need to:
On another Windows computer, go here and download the media creation tool by clicking on Download tool now.
Install the media creation tool.
Open the media creation tool.
Select For another PC.
Follow all the onscreen instructions (such as selecting your preferred language and the system architecture – 32-bit or 64-bit – of the computer that you are downloading the Windows 10 setup to) and then download an ISO file for Windows 10 that you can not only use to install Windows 10 but can also burn to a USB or DVD.
Burn the ISO file to a USB.
Boot up the computer that is suffering from the blue screen that says it does not have an Operating System, access its BIOS settings or UEFI settings and change its boot order so that it boots from a USB. Save the changes, exist the BIOS, insert the USB that contains the Windows 10 setup and then shut your computer down.
Power your computer up. It will boot from the USB that you inserted, so press any key to get the computer to start installing Windows 10.
Enter your language and other preferences, click on Install Windows, enter your product code or click on Skip in the next window if the copy of Windows 10 you were using before was already registered, agree to the license terms, choose to have a Custom installation, select the partition that you want to install Windows 10 on and format it, click on Next and then follow the rest of the installer’s instructions to successfully perform a clean install of Windows 10 on your computer. After a fresh install of Windows 10, you will no longer see a blue screen stating that your computer does not have an Operating System every time you restart it.
Also see how to create a Bootable ISO using Rufus.