Windows 10 Missing Operating System Error

Windows 10 may sometimes welcome you with a bizarre “Missing operating system” error when you boot up your computer. How come there is no operating system installed on your machine? Keep on reading this guide to learn more about this bizarre error.

How Do I Fix a Missing Operating System Error?

This error usually occurs if your hard disk is damaged or the master boot record is not working properly. Let’s see how you can fix this problem.

Disconnect All Peripherals

The first step is to disconnect all the peripherals. This includes your external storage devices, mouse, keyboard, and so on. Use only your laptop’s built-in keyboard and trackpad as input devices. Of course, if you’re using a desktop computer, keep your mouse and keyboard attached. If this solved the problem, plug in your peripherals one by one to identify the culprit.

Create a New Windows 10 ISO File and Rebuild BCD

1. Go to http://www.microsoft.com/en-us/software-download/windows10.
2. Go to Create Windows 10 installation media to generate a new Windows 10 ISO file.
3. Then insert the installation media. Select Repair your computer. The option is available in the lower left-hand corner of the screen.
4. Navigate to Troubleshoot → Advanced Options → Command Prompt.
5. Check the disk partition for errors by entering the following command: chkdsk/f /r C: and replace C with your actual drive letter.
6. Then rebuild the BCD store with the help of the commands below:
   • CMD> bootrec /scanos
   • CMD> bootrec /rebuildbcd
   • Continue with the CMD> bootrec /fixmbr and CMD> bootrec /fixboot commands.

Mark the Main Partition as Active

If your primary partition is not active, that could explain why your computer could not find the operating system files.

1. Go back to Troubleshoot → Advanced Options → Command Prompt to activate the main partition.
2. Then run the diskpart command in Command Prompt.
3. Next, enter the list disk command.
4. Select the drive where you installed the Windows 10 OS files. Let’s say it’s disk 0.
5. Then run the commands below:
   • select disk 0
   • list partition
6. The list of all the active partitions should now be visible on the screen.
7. Locate the System reserved partition.
8. Enter the command below to activate it:
   • select partition [enter the partition number]
   • active
9. Restart your computer and check if the OS is still missing.

Conclusion

To sum up, Windows 10 users may occasionally get the “Missing operating system” error shortly after upgrading their OS. The error is usually triggered by peripherals conflicting with the new OS, a damaged hard disk, or master boot record issues.

We hope that the three solutions listed in this guide solved the problem. Do hit the comments below and tell us more about your troubleshooting experience.