When you turn on the laptop operating system found. Operating system not found: what is this error and how to deal with it. Disconnecting external USB devices from the computer

Hello, dear friends! The next time you start the computer, an error appears on the monitor with the name “ Operating system not found". Instead of loading Windows, a message is displayed on the screen, which, translated from English into Russian, means that the system was not found.

For many, such a mistake causes negative emotions, but everything is not as scary as it seems at first glance. Let's consider in order what this error is, why it appears and how to fix it on your own, without turning to qualified specialists for help.

Error “Operating system not found” - what does it mean?

“Operating system not found” - what could this mean? After all, Windows OS is installed on the computer, and before this it started without problems. This error usually occurs after the user has manipulated the hard drive, for example, changing it to another or a new one. If the user has not done anything like this, then the reason may be a failure of the hard drive or a problem with connecting the cable.

The second probable cause of the error is incorrect setting of BIOS parameters.

Most often as incorrect installation BIOS settings is the location of the HDD or hard drive not in the first, but in the second place. Initially, you need to make sure that the cable is connected to the hard drive, and only after that you need to go to Bios to check that HDD is in the first place of launch.

Check to see if there is a flash drive inserted into the computer that is trying to start the computer. The error message appears on various versions of the operating systems WindowsXP, 7, 8, 8.1 and 10. If the problem occurs on a laptop, then the probability of the hard drive failing is 90%. To try to eliminate the error, you need to do a number of manipulations. Why try? Because at the same time we will look for the cause and try to fix it, unless of course the whole point is the failure of the hard drive.

I How can I fix the “Operating system not found” error?

If checked system unit for absence of defects with connecting hard disk, then turn on the computer and boot into the BIOS. You need to check whether the settings in the BIOS are set correctly, and if not, then it is enough to change them to return the computer to working order.

To get into the BIOS, you need to press the F2 or F12 key while starting your computer or laptop. After the blue screen appears, where everything is written in English language(this is the Bios shell configuration), you need to go to the Boot section using the arrows on the keyboard.

This is interesting! For those who have never been to the BIOS system, it will be useful to know that this shell is controlled only using the keyboard, and the mouse is inactive here, but in new versions of the OS the mouse is still active (an example will be discussed below). new version BIOS).

After going to the Boot section (on some Advanced versions), a list of devices connected to the computer will appear. The name of the hard drive should come first. If this is the case, then the cause of the problem is not in the BIOS configuration. If the hard drive is in the second or other places, then the problem has been found. You can fix it in the following way:

1) Highlight the hard drive name in white using the up/down arrows.

2) Press Enter, then move the hard drive to the first place.

3) Save the settings.

Now you can exit the BIOS section and boot into Windows. In 100% of cases it is sure to load after performing the above steps.

II Resetting settings in BIOS

If, after entering the BIOS, the hard drive is placed in first place in the Boot section, then you can solve the problem by resetting the settings to factory settings. Any version of the Bios shell has settings that can be implemented different ways. Let's consider one of them:

— Open the Exit section.

- Find the LoadSetupDefaults item in it.

Save the completed actions, after which you can leave the Bios shell and launch Windows.

After completing these steps, the computer will return to factory settings. If the problem was software, and Windows did not boot precisely because of it, then resetting to factory settings will help resolve the problem. If not, then move on to implementing another method.

III Switching the hard drive operating mode

If the “Operating system not found” error appears on a laptop where access to the hard drive is limited or difficult, then you will need to look at the settings for the operating modes of the hard drive. The SATA configuration has two modes - AHCI and IDE. When you first install the OS, the default mode is AHCI. If you switch the mode to IDE, you will not be able to install Windows on your computer.

If, after installing the operating system, users experiment with the BIOS shell and accidentally change from AHCI to IDE mode, then the OS will not start after making such changes. When starting, the error “Operating system not found” will appear on the monitor. If such actions are appropriate, then you need to change the settings, and then restart Windows.

IV Restoring MBR hard drive

Another reason for the formation of the “Operating system not found” error may be a violation of integrity sectors of hard disk. The error can be corrected by repairing sectors. You can do this yourself using a USB flash drive or boot disk. I suggest you consider this using the example of the tenth Windows versions.

Instructions for restoring hard disk sectors look like this:

After starting from a flash drive or disk, you need to select “System Restore”.

Follow the path: Troubleshooting - Advanced options - Command line.

After this, you need to enter three commands in order, which are described below:

bootrec.exe /fixmbr

bootrec.exe /fixboot

bootrec.exe /rebuildbdc

Close the command line and restart the computer, only from the hard drive. The problem will be fixed if the cause is damaged sectors of the hard drive on which the Windows OS is recorded.

So, to summarize today’s release, which involves eliminating the “Operating system not found” error yourself, you will need to carry out the following manipulations:

— Check the BIOS settings, move the hard drive to first place and, if necessary, reset the data to factory settings.

— Check the connection of the loops.

— If a fault is detected in the power supply, if it does not supply power to the hard drive, you need to replace it.

— Check mode work hard disk in BIOS and switch it to AHCI.

— Restore damaged hard drive sectors.

In conclusion, I hope that today’s instructions will definitely help solve the problem with the error. If after these steps the hard drive refuses to load the OS, then you need to check it for suitability and, if necessary, replace it with a new one.

It's always unpleasant when, when you turn on your computer, an error appears on a black or blue screen instead of the usual working one. Windows desktop. In this case, users are concerned about a problem on a black screen that prevents the system from loading, or rather, the error says that there is no system at all. You can see her in this image: . It is written that operating system not found, let's figure it out.

What to do with the Operating system not found error

Why does this problem occur? The main culprit of the problem is related to the hard drive and for most, although rarely, the cable simply came off from the connection port to system board or the HDD itself. The second point is that the BIOS parameters are set incorrectly. For example, your hard drive is not in first place, but in last place, or some other options have been changed. Also, any faulty component, be it a power supply or something else, can affect the appearance of this error.

Now on a contract basis. Check the BIOS for incorrectly set options. On the tab Boot or Advanced Make sure the hard drive (HDD) is in first place. If this is not the case, then rearrange using the arrows or the F5 and F6 keys, depending on the BIOS version. If the settings are all correct, then simply . This will not make it worse, but the error may disappear.


But what if the hard drive is not displayed at all in the BIOS? There are two options. I said at the beginning that the disk could have been disconnected by an unknown force, or the cable could have simply come loose. You need to completely turn off the computer and check all the wires to see if they are connected tightly. The second option is a malfunction hard drive. There is nothing left to do but check its functionality from another PC.

When operating system not found appears on a laptop, there is a very low probability that wires and cables will come loose, since everything is tightly and compactly located there. Most likely your disk is simply faulty, or there is a problem in the BIOS.

Software solutions

Above, we looked at physical solutions, and now let’s see how this can be fixed programmatically.

The next one common problem The problem is that another one could have been installed on the hard drive where the operating system is installed. More precisely, try to do it. Eventually boot record The old OS was overwritten by the new one, but it so happened that more than one OS does not boot and the operating system not found error appears. To fix this problem you need to restore Windows boot loader.

The last solution, although it is not a software solution, I’ll add it here in the end - replacing the power supply. It could either be completely faulty (although I doubt that the computer would start after that) or partially faulty.

Let's summarize what was written about this error:
  • Reset BIOS settings;
  • Move the hard drive with the system to the first place in the list of devices;
  • Check the cables and wires connecting to the HDD to see if everything is tightly connected;
  • At faulty disk, make sure of this. Connect to another PC (the disk may not be detected in the BIOS);
  • Replacing a faulty power supply;
  • Repair bootloader

Now you know about the basic solutions to the operating system not found error. I indicated the necessary links, otherwise I would have to rewrite what already exists. I hope this helps you and good luck! By the way, I wrote another article. Read it, maybe the instructions there will help you too.

Sometimes Windows Update fails and the operating system stops loading. This can also happen when more than one version of Windows is installed on the same computer. We offer one of the options for solving the problem with system loading.

To perform the procedure for restoring your computer, you will need a Windows installation CD or Recovery CD for Windows.

  1. Insert the Windows disc into the drive
  2. Restart your PC
  3. Enter BIOS
  4. Change boot order - priority to boot from CD/DVD
  5. Save and restart your computer
  6. Select your language and then click Next
  7. Click on the System Restore button
  8. Select your operating system, most likely there will only be one system listed, then click "Next" again
  9. Select "Use recovery tools that can help fix Windows problems" and click "Next"
  10. Click "Start Repair"

Your computer will restart again. Take the drive and change the boot order in the BIOS back to the hard drive first. Windows should boot.

At this point, try running Windows updates again and see what is needed to install them. If the problem occurs again, try repeating the first 8 steps above. After selecting the operating system, click Next.

  1. Click "Open Command Prompt".
  2. Enter " FIXMBR" (Windows XP) or " Bootrec.exe /FIXMBR" (in Windows 7).
  3. Press Enter.

Restart your computer and check which recovery option worked.

Please note that if, when selecting a system, your operating system does not appear, then most likely your hard drive is faulty. There is only one way out - replacement of hard disk onto a working HDD.


One of the most terrible user errors is the one that appears when turning on the computer and tells us, on a black BIOS screen, that "". When this message appears, our system will not be able to boot, and the only way out is to restart the computer by pressing “ctrl+ alt+del”, and you will most likely see this message again.

The problem with the error is that the operating system is not displayed and therefore the BIOS cannot boot the Windows system. The reasons for this error are very varied: from a simple configuration error in the BIOS to a more serious problem that, in the worst case, forces us to completely format the computer. Therefore, we will analyze the main reasons and their solutions to eliminate the error "" ( An operating system wasn't found).

Disconnecting external USB devices from the computer

If your computer has multiple internal hard drives, external drives, and USB flash drives connected, it is likely that BIOS is trying to find the operating system in the wrong place. Consequently, not detecting the Windows system, it displays the error “No operating system found.”

  • To solve this problem, you need to disable everything external devices storage devices connected to the USB ports and try again. We can also check our optical drive to make sure it is not trying to load the wrong DVD.

If after doing this the problem is still not resolved, the next step is to go to BIOS settings.

Changing BIOS boot priority

Enter the BIOS configuration by pressing the F2, F12 or Delete buttons. After that, go to the configuration section Boot and put it first in the column Priority a hard drive on which the working and main Windows operating system is located. IN different versions BIOS is called differently, but you are looking for the word with the combination Priority, which means “priority boot”. Here are a few names from different BIOS: Hard Disk Priority, Boot Device Priority, Hard Disk Boot Priority.

After you have set the boot priority from the hard drive on which your system is located, do not forget to save the settings using the F10 button and restart the computer to make sure that the system is “found when you turn on the computer.”

Enable or disable Secure Boot

If you are using modern computer with an operating system such as Windows 8 or Windows 10, then perhaps the reason why our Windows does not start is V incorrect setting UEFI Secure Boot.

Go back to BIOS, find the configuration section Secure Boot (Secure Boot) and deactivate it or activate it if it is disabled to check if the "Operating system not found when starting the computer" error disappears.

In different versions of BIOS or UEFI, the location of the settings looks different, but in any version of the BIOS you look for the column Secure Boot, try disabling or enabling.

Reset BIOS to factory settings

At the bottom of the BIOS menu you will see a key for default settings or reset BIOS. On my car this is F9. Confirm your decision when prompted and restart your computer.

If you haven’t found an example button like F9 to reset settings to factory settings, then look for the line Load Setup Default and reset the BIOS.

If your hard drive with the operating system is placed first, but the computer still does not boot, it is possible that some of the initial sectors of the drive have been damaged, such as master boot record(MBR), DOS boot entry(DBR) , or Boot Configuration Database(BCD).

Repairing these sectors is quite simple. All we need is to create an installation Windows flash drive and through it enter Extra options downloads.

Type the following commands into CMD in order by pressing enter. Each command may take time to complete.

  • bootrec.exe /fixmbr
  • bootrec.exe /fixboot
  • bootrec.exe /rebuildbcd

Activate the Windows partition

It is possible that the partition on which Windows is installed is disabled. You can fix this using your own tool diskpart Windows. To complete the next steps, you will again need a USB stick for Windows installations. Run the command line as described above, via a recovery disk or Windows installation flash drive and enter the following commands in the command line:

  • diskpart- Launch the tool.
  • list disk- List of connected drives to the computer.
  • select disk 0- Select the hard drive on which you want to activate the partition. In my case, the main hard drive is 0.
  • list volume- Shows partitions on the selected hard drive.
  • select volume 2- Select a local disk for activation. Choose the one where the widows system itself is installed.
  • active- Activate the section.

Restart your computer and make sure the error when turning on the computer disappears An operating system wasn't found. Try disconnecting any drives that don't contain an operating system. Press Ctrl+ Alt+Del to restart, which means operating system not found, press ctrl+alt+del to reboot.

Operating room users Windows systems We are already accustomed to seeing messages with some kind of error instead of the loading screen from time to time. The types of problems vary, but in any case they require urgent action. The operating system not found error can be found on both laptops and desktop computers. The user sees this inscription on a black background, after which the system does not boot. Or rather, the computer reports its absence. Of course, this is not true, and the problem can and should be corrected. Let's figure out what caused it and what to do.

Resolving the Operating system not found error.

As already mentioned, the “operating system not found” error literally means “the operating system was not found.” There may be several reasons:

  • Hard drive failure or incorrect connection train;
  • Incorrect BIOS settings;
  • Problems with the power supply or motherboard.

Let's look at each aspect in detail.

Error correction methods

What should you do first when “operating system not found” appears? You can find out the reason step by step by checking all the components necessary to boot the OS one by one.

It’s better to start with the most harmless thing – checking the settings. Most often, this error occurs in cases where the hard drive priority is set incorrectly. For example, a flash drive is inserted into a computer or laptop, and the BIOS has priority on USB drives. Also, the reason may be an incorrectly connected cable, especially if you changed or reconnected the hard drive the day before.

To check the priority for downloading, do the following:

  • Go to BIOS;
  • Select the Boot tab (sometimes Advanced);
  • Let's check where it is hard drive HDD(must be on the first);
  • If necessary, we rearrange it using F5, F6 or arrows, depending on the BIOS version.

ADVICE. If the settings are correct, try resetting the BIOS. No new errors will appear because of this, but this particular one may disappear. We will tell you how to do this below.

Reboot the system and check if it helps. If not, move on.

Hard drive problems

In cases where the error “an operating system wasn’t found” is still displayed, or the BIOS does not see it at all hard drives, then there can be two reasons:

  1. The hard drive or cable is disconnected;
  2. The hard drive is faulty.

In the first case, you need to completely turn off the PC and recheck all connections. In the second case, all that remains is to connect the hard drive to another computer and see if the error occurs there.

ADVICE. The density of the elements in the laptop does not allow the cable to move away, so the likelihood of solving the problem on the laptop in this way is extremely low.

So, you double-checked everything, but the problem still persists. There is no need to panic, there are a couple more ways to resolve the issue.

Resetting BIOS settings and installing fresh firmware

As we mentioned earlier, a factory reset can help. They are called Default and are available on all versions of BIOS. There are times when the system sees the hard drive and detects it, but does not boot it. The first thing to do is check its status. If opposite the hard drive there is Exclamation point, this indicates that the disk is disconnected or not used. Enabling it is simple:

  1. Select the problematic hard drive;
  2. Find the Specific Item Help field (this is the device help tab);
  3. Let's see what keyboard shortcuts you can use to turn on a specific device.

ADVICE. The combinations differ on different BIOS versions, but most often it is the Shift+1 combination.

After this, the hard drive should turn on and the computer should start without problems. If this does not happen, we try other methods.

A damaged Windows bootloader can also cause not only an error, but a complete system crash. You can try to restore it using installation disk or recovery disk.

  1. Insert the source into the drive;
  2. Launch the BIOS and select the optical drive there as the priority boot device;
  3. Select the recovery console.
  4. We are trying to restore the boot mode and check the disk for errors with the possibility of automatic recovery.
  5. Alternatively, you can use command line, entering bootrec.exe /FixMbr there, and then bootrec.exe /FixBoot. Don't forget about the Enter key after each line.

ADVICE. If your C drive is equipped with an NTFS file system, try using chkntfs /x c: as a check tool.

If you've tried everything and haven't gotten any results, be sure to diagnose your hard drive. In the case of a laptop, you will have to go to a workshop, since attempts to remove it on your own can aggravate the situation. Try using HDD utility Regenerator for hard drive recovery, but the success rate is low. Well, the faulty hard drive must be replaced and the entire operating system reinstalled.

We hope you didn't have to resort to help computer services and managed to fix the problem myself. Ask any questions you have in the comments.