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Fix An operating system wasn’t found on windows 10

How To fix An operating system wasn’t found Windows boot error

Most Of the windows users report An operating system wasn’t found during the boot process. This mostly occurs After upgrade to windows 10 or Perform System Restore. The operating system wasn’t found is very common error found in Windows operating system. 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 Full Error message like

“An operating system wasn’t found. Try disconnecting any drives that don’t contain an operating system. Press Ctrl+Alt+Del to restart”

Mostly The An operating system wasn’t found Boot error can be displayed on Windows 10, Windows 7 or 8.1 computers, after a Windows upgrade (e.g. from Windows 7 or 8.1 to Windows 10), a BIOS update, after you have cloned your hard drive to another disk or After performing System Restore.

Why This An operating system wasn’t found Error

When This An operating system wasn’t found error occurs There may be problem with your computer hard disk, inappropriate or incorrect BIOS settings, damaged or corrupted HDD, and the last thing might have partition something wrong and your disk become deactivate.

The basic input/output system (BIOS) does not detect the hard disk that installs Windows.
The hard disk failed either physically or logically.
Users make inappropriate or incorrect BIOS settings.
Windows Master Boot Record (MBR) located on the hard drive is damaged or corrupted.
The partition which saves Windows boot files is no longer active or users set wrong partition active.

How To Fix an operating system wasn’t found Error

If you are alos suffering from this problem and looking for solutions, Here we have some best working solutions to fix an operating system wasn’t found Error permanently. First Start with basic Troubleshooting disconnect All connected external Devices include the power supply and VGA cable. ( For Laptop users simply remove the battery ) Now press and hold the power button for 30sec. Now only Connect the power supply and VGA cable ( laptop users insert the battery ) and turn on the computer. Check problem fixed If not follow next step.

Set Hard Disk As first boot device

Also, most of the times change the boot device order Set your internal hard drive as the first boot device on the BIOS Setup settings will fix an operating system wasn’t found Windows 10. Note you must disconnect any other USB drives connected to your system. You can change the boot device sequence by fallowing bellow.

Turn on the power button and Press Del key ( F2, F12 or Esc for Different Bios manufacturer ) While bootprocess. You wil present the BIOS setup screen. Here use Arrow keys

Set Hard Disk As first boot deviceUse Right arrow key and move to boot option tab, Here change the 1st boot device as your internal HDD. Press F10 to save this will Restart windows Now check the problem An operating system wasn’t found was solved If not fallow next step.

Perform Windows Startup Repair

If both options Failed To Fix Then you can Perform Windows Startup Repair and let windows to fix the problem Itself.

Create Bootable Media

As Due to this problem you are unable to Boot so you must Require a bootable media to perform Startup repair or feature troubleshooting steps. If you Don’t Have Bootable media then you can create one by fallowing How To Create A Bootable DVD/USB Using Media Creation Tool

Perform Startup Repair

After create Place the Windows Boot Media on the computer and boot from it. To boot from Boot media Access BIOS setup by press Del key. change the boot sequence first boot as CD/DVD ROM press F10 To save and Restart. On Next boot this will display press any key to boot from CD or DVD…  This will boot windows from installation Media.

Here At the first setup screen, choose your Language, Time – Currency and your keyboard input method and click Next. Now on the next screen select Repair your computer.

windows 10 repair your computer
This will restart windows now next click Troubleshoot –> Advanced options –> Startup Repair.

Windows 10 startup Repair
Wait while Windows diagnosing and fix problems. When the Startup Repair is completed this will automatically Restart windows and try to boot in Windows normally.

Also Read : Fix Automatic repair couldn’t repair your pc On Windows 10

Repair Corrupted Boot Files

If all above methods failed to fix operating system wasn’t found Then we have to perform some Advanced Troubleshooting steps like Repair Corrupted Boot files using command prompt to Fix this problem permanently. Lets see How to do this,

You can access Command prompt by accessing the Advanced Boot options. Or you can use new created installation media and boot from this.  same on first setup screen, choose your Language, Time – Currency and your keyboard input method and click Next. Now on the next screen simultaneously press the SHIFT + F10 keys to open the command prompt.

Here At the command prompt window, type command diskpart and hit enter key to open DISKPART utility. Now Type list disk and hit enter key to find out if your disk is set to GPT or MBR partition.

check disk partition is gpt or mbr

Look at the GPT column to see if it has an asterisk (*).

– If you see an asterisk (*), that means that your disk’s Partition Table is GPT.

– If you don’t see an asterisk, that means that your disk’s Partition Table is MBR.

Now Fallow bellow We have two Different solutions for different partitions. ( MBR Partition table and GPT Partition Table )

Fix Boot Files on MBR Partition Table

Note : if you have GPT partition skip thi and Fallow next step

Now find out the Drive letter where windows installed. You can do this by type command type list volume and hit the enter key. you will notice the Drive letter where windows is installed as Boot.

Now When you find out which drive contains the Windows folder, (For me its drive “C:”), give the following command to create the boot files on that drive and press Enter.

bcdboot C:\Windows /S C:

* Note: If Windows are located on a different drive, change the letter C with that drive letter.

After execute the command Again open DISKPART utility by type command diskpart and hit enter key. Here on disk part utility type list disk press enter key.
Select the disk letter by using command select disk 0 

Type Fallowing commands one by one as per instructed bellow

list volume
select volume 3  ( Here select the volume number which contains the windows operating system )

command to fix MBR patition
Type exit to close the DISKPART tool. Thats all now remove the installation media and reboot your computer.

Fix Boot Files on GPT Partition Table

If you have the GPT partition Table fallow bellow.

Type diskpart and hit enter to open the diskpart utility and type bellow command.
list disk
select disk 0 ( Select the disk number ).
Next type command list partition and hit enter key.
Here Find out which Partition is labeled as System. And Select the System partition by type bellow command

select partition X (Where “X “is the number of the partition labeled as System. e.g. “4”).

Assign a drive letter (e.g. the letter “H”) to the System partition by typing the following command and press Enter: *

assign letter=H:

* Note: If the drive letter “H” is already used, then give the next drive letter in alphabet.
type exit and press Enter to close DISKPART tool.

Again Type Bellow commands one by one

cd /d H:\EFI\Microsoft\Boot\
ren BCD BCD.bak
bcdboot C:\Windows /l en-us /s m: /f UEFI

Note : Change the letter “H” if you have assigned a different drive letter to the System partition.

Thats all Remove installation media and Now Close all Windows, reboot your computer. Check problem solved.

If all above methods failed then the check by perform windows clean installation.

These are some Best working solutions to fix An operating system wasn’t found Boot error on windows 10, windows 8.1 and 7 computers. Have any query, suggestion feel free to comment bellow.

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