Unfortunately, sometimes you can encounter quite serious problems with turning on computers and starting operating systems, although up to a certain point no troubles foreshadowed. It happens that the computer does not turn on at all, but most often the computer turns on, but the operating system does not start. It is precisely such situations that will be discussed later. Consider issues related to why the computer does not boot, and what to do in such situations. There are several universal solutions.
The computer turns on, but the operating system does not start: reasons
Among all possible situations where failures occur at the loading stage, several typical cases can be distinguished.
There are three options:
- a black screen appears;
- BSoD blue screen appears;
- the operating system starts, but cannot fully boot.
In the first case, when the computer does not start (the download does not turn on), messages may appear on the black screen indicating physical or software problems. In the simplest case, when nothing serious happens, the system may report that, for example, there is no keyboard (for desktop PCs). The simplest solution is to connect it and reboot.
If the computer turns on, but the download does not start, and instead warnings about software failures or missing files appear on the black screen, there can be many reasons for this system behavior. Among them, first of all, there are problems with the hard drive, damage to the operating system (accidental or intentional deletion of system components or registry entries), virus exposure, incorrect boot sector entries, RAM conflicts, etc. By the way, if a blue screen pops up, this is more related to the "RAM" or recently installed device drivers, which cause conflicts not on the software, but on the physical level.
What to do if the computer does not boot and the operating system does not start for the above reasons? Depending on the situation, there are several solutions. To an uninitiated user, they may seem quite complicated, but in certain situations, only them can be used to resuscitate the system. Therefore, you will have to spend both time and effort.
The computer turns on, but does not boot: what to do first?
So, let's start with the simplest. Assume that a short-term technical malfunction occurred in the system, for example, due to incorrect shutdown or voltage drops.
As a rule, almost all of the currently used modifications of Windows usually when restarting automatically activate the start of system recovery. If this does not happen, before starting the system you will have to use the F8 key to call up the additional boot menu (in Windows 10 a different method is used).
The computer turns on, but the operating system does not start? Do not be upset. Here, in the simplest version, you can select the download line of the last working configuration. If everything is in order with the system components, the system will boot without problems. If this does not help, you will have to use the troubleshooting section, and sometimes even an attempt to boot in safe mode may succeed.
Possible viral infection
Unfortunately, viruses can also cause such situations. What to do if the computer does not turn on? Ways to solve this particular problem boil down to using a powerful anti-virus scanner that could check for threats even before the OS itself starts.
Among the variety of antivirus software, it is worth mentioning separately disk utilities that start directly from optical media or USB devices, have their own boot records and even a graphical interface like Windows. One of the most powerful tools can be called Kaspersky Rescue Disk. Its use can guarantee almost one hundred percent detection of viruses, even hiding in RAM.
RAM conflicts
Now let's see what to do if the computer does not boot, and instead a blue screen appears. As already mentioned, most often this indicates problems with drivers and RAM. We don’t touch the drivers yet, but let’s look at the “RAM”.
The proposed solution to the issue of if the computer does not boot up is mainly designed for stationary PCs. In this situation, you should remove all memory bars, and then insert them one at a time and check the load. Perhaps some of them is the link that causes failures. This can be observed when trims of different manufacturers are added.
If the system manages to somehow load using the same safe mode, the “RAM” should immediately be checked with the Memtest86 + utility, which will help identify the true cause of the problems.
The system does not see the hard drive
Now the worst situation is when the computer does not boot. Causes and solutions may be related to the hard drive.
Winchester can have problems both software and physical, although sometimes this is not even the case. The problem can be quite commonplace: the user has the BIOS settings set the boot priority from a removable device, for example, from an optical disk, which is currently in the drive, but is not a system one. It should simply be removed and the download repeated.
On the other hand, another problem that the computer does not start (the system does not start) can be due to the fact that the bootloader and the records of the corresponding sector are damaged. A solution to this situation will be discussed later. But in the simplest case, you can try to recover disk data using Recovery utilities.
Sometimes it helps to change the settings of the primary BIOS I / O system. Here you need to find the section related to setting up the hard drive, and deactivate the use of AHCI mode in the SATA configuration parameters.
Finally, a hard drive can also have purely physical damage, and here you can not do without outside interference.
Using the installation disc
Many users clearly underestimate the help that an installation or boot disk with a system image can provide in solving problems associated with situations when the computer turns on but the operating system does not boot.
Firstly, almost any kit includes the so-called recovery console, with which you can fix a lot of software failures, and secondly, you can use the command line here. This, by the way, is the most effective method. Next, it will be understood how this works.
Problems with the BOOTMGR bootloader
It is believed that the most common problem when the computer turns on but the operating system does not start is damage to the Windows boot loader (Boot Manager). In this case, the system just writes that there is no system partition (it simply does not see the hard drive).
You can fix this problem provided that you start from the boot disk and go to the command line in the recovery console, to call which you must press the "R" key. Next, you must first use the disk check command, and then fix (restore) the boot records.
The whole sequence is as follows:
- chkdsk c: / f / r;
- Bootrec.exe / FixMbr;
- Bootrec.exe / FixBoot.
After entering commands, punctuation marks are not put, and the enter key is pressed. If for some reason the execution of these commands did not have a positive effect, as an option, you can use the complete rewriting of the boot sector, which is performed by the Bootrec.exe / RebuildBcd command. If the hard drive does not have physical damage, this should work, as they say, one hundred percent.
You can use some third-party utilities. The most suitable program is a tool called MbrFix, which is part of the Hiren's Boot CD boot kit. After calling it, for example, for Windows 7, provided that this system is installed, and only on one disk (there is no partitioning), the following should be written:
- MbrFix.exe / drive 0 fixmbr / win7.
This will save the user from having to make changes to the boot entries, and the download will be restored.
Problems accessing the NTLDR file
When a message appears that this component is absent in the system, the boot fix is applied first, as in the previous case.
However, if the result is not achieved, you will need to copy the original file to the root of the system partition. For example, if it is drive “C” and drive is “E”, the command will look like this:
- E: \ i386> copy ntldr C: \ (after copying, the system will boot without problems).
Corrupt or missing HAL.dll file
In the case when the computer turns on, but the operating system does not boot in normal mode, the cause may be the damaged HAL.dll component (the corresponding notification can be displayed on the screen).
In this situation, you need to boot the system in safe mode, call the command console and write the following line in it:
- C: \ windows \ system32 \ restore \ rstrui.exe (then press the Enter key and restart).
Instead of a total
That’s briefly all that concerns the solution to the problem of the impossibility of starting the operating system. Naturally, the issues that could be caused by low power, a CMOS battery failure, loose loops, the presence of dust inside the system unit or other malfunctions were not addressed here. But programmatically, the above methods work flawlessly.