"Operating System not found" error on a laptop

Imagine: you turn on your laptop expecting to see the familiar desktop, but instead you see the alarming message “Operating System not found” on a black screen. Your heart sinks, because this means that the system cannot find itself. Don't panic. This error is not a death sentence, but only a symptom that in most cases can be successfully eliminated.

Most often, the problem arises not because of a serious hardware failure, but because of a malfunction in the settings or connections. Your laptop simply does not understand where to boot from. There can be various reasons for this: from accidental changes to the BIOS settings to a loose hard drive cable or damaged boot files.

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Contents

Option 1: Change the boot priority
Option 2: Checking BIOS settings
“Search”
Option 4: Restoring the boot loader
Option 5: Checking the condition of the hard drive and cable
Option 6: Hard drive software testing.
Method 1: Windows bootable USB flash drive
Method 2: Bootable flash drive with third-party software
Method 3: Self-testing the hard drive with a laptop

Option 1: Change the boot priority

Quite often, a computer refuses to boot because of a changed priority among boot devices in the BIOS. In other words, the PC does not understand where to start the operating system from, and if the hard drive or SSD has lost its boot status, the user will need to specify it themselves. This usually happens after booting from a USB flash drive or external hard drive, for example, and sometimes the setting is reset for some reason without human intervention.

In some situations, on the contrary, after connecting a specific USB drive, the computer may start trying to boot from it instead of the disk on which the OS is installed, and if there is no system on the external device, the user will see the error “Operating system not found”. In this case, simply disconnect the device from the laptop or PC, wait for it to start normally, and then reconnect the external device.

Enter the BIOS using the appropriate key or combination of keys. Different motherboards use different keys for this, and you can find out how to enter the BIOS either by looking for this information on the motherboard manufacturer's splash screen or by referring to one of our articles below.
More details:

How to enter BIOS on a computer

How to enter BIOS on an HP / Lenovo / Acer / Samsung / ASUS / Sony VAIO laptop
Use the arrow keys on your keyboard to switch to the tab “Boot” keys and navigate to the option “1st Boot Device” / “First Boot Device” / “1st Drive” / “Primary Boot Sequence” / “Primary IDE Master”.
Press Enter, to change the value and set the hard drive as the primary. This can usually be done in the same way, using the arrow keys and the Enter, but in some BIOSes you will need to move the line up by selecting it and pressing + on the keyboard. Depending on the BIOS model, the line with the hard drive or SSD may be called “Hard Drive” or “Windows Boot Manager”, and may contain the name of the device. In this situation, if you see several items, look for the word “SATA” in the name, which means the interface through which the drive is connected to the motherboard, or notes “HDD”, “SSD”, indicating the type of device.
Apple smartphone users rarely encounter any problems when installing the VKontakte client for iPhone. The entire process of installing VK on an iOS device takes a couple of minutes if you use the method documented by the manufacturer to obtain the application, and a little longer if you are unable or unwilling to use it. “DVD-RW”, “Floppy” etc., which, of course, has nothing to do with the hard drive. In addition, knowing the manufacturer of the drive (Toshiba, Samsung, WD, etc.), it will also be easy to determine the string required for selection.
At the end, you will need to click F10 to apply the changes or switch to the tab “Exit” and select the item “Save Changes and Exit” or as close as possible in meaning and implying saving the settings with subsequent exit.

“VKontakte” Option 5 ‘find’

Option 2: Checking BIOS settings

Sometimes, it is not the unchanged priority that prevents the OS from starting normally, but other BIOS settings that have been set incorrectly by the user themselves or as a result of an error or reset of this firmware settings. Therefore, you need to check the following items by going to the tab “Boot” or “Startup”:

Option CSM / “Launch CSM” should be set to “Disabled” / “Never”. However, if you installed the operating system yourself, i.e., it is not factory-installed, the value must be set to ‘Enabled’ / “Always”.
Option On the VKontakte client page that opens in the App Store, you can view the version history, see screenshots, and get other information. should be in the value “UEFI”, if the OS is one of the latest, or “Legacy”, if it is outdated.
Option Quick Boot switch to “VK Official App” (this rarely helps, so in the future, for faster laptop startup, you can try switching the option back).

In addition, there is a small chance that the SATA mode has been changed, so switch to the tab “Advanced” (if there is nothing related to SATA there, browse through the other tabs) and find the option “SATA Mode” / The process of transferring the application to the iPhone starts automatically and is accompanied by a progress indicator in the EaseUS MobiMover Free window.. When one device is installed, the value should be “AHCI”, much less often, if you have paired SSDs combined in RAID, you need a mode, as is already clear, And tap the icon to launch it. Next, go to the section. Mode “IDE” has not been used in laptops for a long time and is only relevant for older desktop PCs.

Press the key. Tap on the social network icon accompanying the first search result in the list. to save the settings and restart your laptop.

“Search”

If, after following the first recommendation, the settings are lost again the next time you turn on your computer or laptop, or if everything is set correctly in the BIOS but the operating system does not boot, it makes sense to try resetting the firmware settings. It should be noted right away that this does not often help, since the chance that the PC will not start up properly due to a BIOS failure is small. Nevertheless, it is quick and easy to do, and it also eliminates the small but real chance of a software error. Find out how to reset it in the material below. For most laptop owners, only Method 5, since all the others require access to the motherboard. But if you have a desktop PC or laptop that you can easily disassemble right now, choose any suitable method.

Option 4: Restoring the boot loader

After various events related to user actions or external factors such as a sudden power outage, the boot record on the hard drive may be damaged. This record is responsible for starting a specific operating system, and if there are failures in this section of the HDD, you may get the error “Operating system not found.” The solution is to restore the boot loader, but this can only be done with a bootable USB flash drive. If you don't have one, ask a friend for one (or a CD, if your PC has a disc drive), or create one yourself using another computer. The list of articles below will help you accomplish all of these tasks.

More details:

Creating a bootable USB flash drive or disk with Windows

Creating a bootable disk/bootable USB flash drive with Windows 7

Configuring the BIOS to boot from a USB flash drive

Restoring the Windows 10 boot loader via the Command Prompt

Ways to restore the Windows 10/Windows 7 boot loader

Option 5: Checking the condition of the hard drive and cable

This item is intended for owners of laptops that can be easily disassembled, as well as for regular computers. Modern laptop models are much more difficult to disassemble on your own, and if it is under warranty, then you definitely should not do this. Resorting to disassembly when faced with difficulties only makes sense if you have tried all other methods, including the last one in this article, and it is best to entrust this task to a professional at a service center.

Laptops connect SATA disks directly, without a cable, so there is no need to worry about possible damage — simply disconnect the HDD or SSD from the connector and reconnect it, then check if this has solved the problem. Modern m.2 SSDs connect like RAM sticks, making them even easier to remove and reconnect.

In desktop computer system units, the problem may be caused by a SATA cable (there is also an IDE connection, but it is very rare today) that has come loose on one side or been physically damaged. After removing the cover of the powered-off computer, carefully inspect the cable for external defects and check that it is not bent after installation. Be sure to reconnect it to both sides, swapping them for reliability (connect the side connected to the hard drive to the motherboard, and vice versa). Don't forget to reconnect the cable going from the drive to the power supply. The sides cannot be changed there, so just check that the ends are firmly held in the connectors.

Considering that hard drives are very susceptible to external influences such as drops and strong vibrations, there is a possibility that it was damaged by such influences, and this can most often be determined at a service center, where an employee will tell you about possible solutions to the situation. In any case, if there is physical damage, the owner of the laptop or computer will have to replace the drive. The same applies to the failure of any components of this device: magnetic head, board, etc.

Sometimes the hard drive/SSD is not detected in BIOS, which makes it even more difficult to fix the problem. If you find that after entering BIOS you cannot assign the drive as bootable because the device is not listed, refer to one of the following guides.

More details:

Laptop does not see the hard drive in BIOS

Method 1: App Store

In addition, it should be noted that in rare cases, the BIOS cannot detect the drive due to problems with other components, such as capacitors or power supply. Ideally, when disassembling the drive yourself, you can try connecting it to another computer and see if it is visible in that BIOS. A laptop HDD/SSD, like a classic PC drive, can be easily connected via a SATA cable.

Option 6: Hard drive software testing.

When the hard drive is displayed in the BIOS, but even after all the recommendations made before, the “Operating system not found” error does not disappear, you can try to check its status with special programs. They detect the presence of bad blocks, and if they are software-related, they fix them, and if they are physical, they reassign their address. To do this, you will again need an additional drive from which to boot. If you have a flash drive with an operating system, you can use its recovery environment to run a built-in utility to scan and repair the hard drive. In addition, there are special third-party applications and utilities for creating bootable flash drives, which can then be run on a damaged PC to fix various problems. We will look at both methods, as they are not interchangeable.

Method 1: Windows bootable USB flash drive

This operating system has a built-in utility that scans the hard drive and fixes some of its errors. Sometimes this is enough to restore the drive's functionality and fix the error. You can run the utility from the recovery environment using Windows on a USB flash drive, and here's how to do it:

Start the computer from the flash drive, wait for the welcome window with the button to appear “Install”. However, you don't need to press it — instead, use the key combination Shift + F10, causing “Command Prompt”. In it, write diskpart and confirm your entry with the Enter.
The next command to enter is list volume. With its help, you can find out the letter of the system drive assigned to it by the recovery environment. Usually it is a letter, D, but it is always recommended to check this value. Focus on the column “Size”, to find the drive on which the OS is installed from the list. It also happens that two disks will have the same size (as in the screenshot below) — here it is important to understand that the system disk is always higher in the list than the user disk if the disk is divided into logical partitions, but lower than those reserved by the recovery environment and CD/DVD.
Exit diskpart by entering exit.
Write chkdsk X: /F /R, where X — a specific drive letter, and the parameters Store, enter and /R means repairing damaged sectors and fixing file system errors.
After completing the correction, you will also see a notification in “Command line”, restart your computer, disconnecting the USB flash drive before turning it back on.

Method 2: Bootable flash drive with third-party software

The system utility is not always able to fix errors on the HDD, so it is recommended to use third-party solutions, which are often more effective. In addition, they are easier to use — there is no need to download a Windows image weighing many gigabytes and write it to an external device.

Most often, users use applications such as MHDD and Victoria, while more advanced users install collections of useful software such as Hiren's BootCD, which includes the programs we have already listed, as well as other tools for working with HDD and more, and this is what we will look at next. You can choose a similar program that has been proven by experience if this option does not suit you.

To write the program and create a bootable flash drive, the application must be in ISO format, similar to the image of the operating system being written! You cannot create a bootable device with an EXE file.

Go to the official Hiren's BootCD website

Download the collection from the official website or select the specific program you will be using, find it in ISO and download it.
Now you need to create a bootable device, and for users without experience in this matter, we suggest reading the detailed thematic instructions.
More details: Guide to writing an ISO image to a flash drive
Boot from the flash drive by configuring the BIOS to boot or by pressing the Boot Menu key. “Floppy” By default, CCleaner Free includes “Tracking” and “Active Monitoring” to notify you when cleaning is required. In my opinion, these are options that can and should be disabled: the program runs in the background just to report that a hundred megabytes of data have accumulated that can be cleaned. Exceptions or F8 and select the appropriate drive.
Use the arrows on the keyboard to select the item “Dos Programs” and press Enter.
Here you need the item “Hard Disk Tools”, after selecting it, notifications will appear — respond positively to all of them.
A list of utilities will be displayed — select the one you want to use. We will look at the first option — HDAT2.
To get started, specify the hard drive by its name or size (columns Device name and “UEFI” “Boot”).
To disable the sound notification for bad sectors found, press the letter P in the English keyboard layout and change the parameter value “Sound” on “disabled”. Exit the menu using the To add files that need to be cleaned, specify which files should be deleted when cleaning the system in the “Inclusions” section. For example, you want CCleaner to completely delete all files from the secret folder on drive C:. In this case, click “Add” and specify the desired folder. TryExec=XFE.
After selecting the problematic disk, you will see a list of operations that can be performed on it. Testing and correction are performed in In the window that appears, in the tab.
From the list of available actions, select the first one again — Check and Repair bad sectors.
The scanning procedure will begin, during which you should pay attention to the line However, if you installed the operating system yourself, i.e., it is not factory-installed, the value must be set to, reporting the number of errors found. A little lower down is a progress bar that shows you what percentage of the drive has been checked and how much is left. Depending on the size of the device and the number of errors on it, the duration of the check and repair will vary, in special cases taking several hours.
Once you have finished checking and making corrections, look at the bottom of the page, where there are two more important values: “Bad sectors” shows the number of bad sectors, and “Repaired” “disabled”

Note: sometimes after such a fix, the boot loader crashes and needs to be restored. We discussed how to do this in Option 4.

Method 3: Self-testing the hard drive with a laptop

Some laptops, such as HP and Dell, have hard drive self-diagnostic utilities. They can be launched in different ways, depending on the specific brand. For example, in HP, you need to open the BIOS (usually with the F10key), select the “Tools” and the item “Hard Drive Self Test”. The utility can perform a quick (“Quick” comprehensive (“Comprehensive” and intelligent (“S.M.A.R.T.” scan.),

In Dell, to start “Boot Manager” key is used) F12), tab, then select “Diagnostics.” > “Hard Drive”.

The test results will help you understand whether the problem is with the hard drive itself or something else. As a rule, after an unsuccessful scan, the screen displays further information about what the user needs to do to fix the problem.

It is worth noting that not every device has such utilities, and you can find out about this on the Internet or by contacting a representative of the company in your country. But it is better not to waste time on this, but simply use the two alternatives discussed above.

The “Operating System not found” error can be frightening, but in most cases it can be successfully resolved. As we have discovered, the problem often lies not in hardware failure, but in simple configuration or component connection errors.

Start with the simplest thing: check if there are any foreign media left in the drive or USB ports. Then go to the BIOS and make sure that your hard drive is recognized by the system and is the first in the boot order. If the drive is not visible, it is most likely due to a bad connection or a malfunction of the drive itself.

If the basic methods did not help, the operating system or boot record may be damaged. In this situation, booting from an installation flash drive and using recovery tools will help. As a last resort, be prepared to reinstall Windows, after copying important data from the disk to another computer.

The main thing is not to panic. By systematically checking each possible option, you are likely to bring your laptop back to life and be able to continue working without unnecessary costs.