As you know, not one of all known Windows operating systems is safe from the appearance of such critical errors and disruptions in their work that sometimes the computer simply stops loading normally. At the same time, notifications may appear that the operating system was not found, and when restoring the bootloader using command line tools, a failure is reported when copying Windows boot files. Usually this applies to modifications 7 and above, but for some reason recently it has been very often observed precisely in Windows 10. The situation, it must be said, is not the worst, therefore, below are some basic methods for eliminating this kind of problems using various means, in the application of which Even the most untrained users should not have much difficulty.
Why does it crash when copying boot files when trying to restore a system?
First, let's find out the nature of this error. It appears exclusively when trying to restore the system from the command line using the BCDBoot toolkit. Why doesn't it work? As a rule, the failure of BCDBoot.exe when copying boot files basically only indicates that there is no (or undefined) active partition on the hard disk that is used to restore the system when a problem occurs with its start.
Apparently, many people know that usually such a section is marked as reserved by the system. This is what the BCDBoot tool does not find.
The nuances of installing Windows 10 on your hard drive
The main reason for the appearance of BCDBoot.exe failure when copying the files necessary for the correct start of the system was sorted out a bit. However, it does not fully reflect the current situation, and here everything may depend on which section the system was installed in. If you installed the same “top ten” on a computer with a regular BIOS and a hard disk with MBR, the system reserves for itself about 350-500 MB. In the case of installing the system on a terminal with a primary BIOS in the form of an updated modification of UEFI, the hard disk has the GPT partition style. In this case, the system reserves approximately 100-260 MB of free disk space. And it is this section that serves as a kind of storage boot configuration (BCD).
What is a BCDBoot?
The tool itself is not only the tool responsible for the correct start of the installed system, but can also be used to quickly restore it to a healthy state. In this case, it does not matter at all whether the OS was installed in the GPT partition or on the disk with MBR.
This applet allows you to restore the MBR bootloader quite simply, but for this, the UEFI mode for the primary input / output system should be turned off, and instead the boot using Legacy should be activated. However, since the system has already been installed, there is no need to change the start parameters in the BIOS.
Another quite common situation is related to the transfer of the working system from an external USB-HDD to a stationary hard drive, when a rollback is required at the end of the transfer. Apparently, the reason for the failure to copy the download files is due to the fact that you simply “forgot” these files on the external drive, or the primary system initially identified it as a priority (first) device, but then it was turned off.
Auto Recovery
Before you take any steps to restore and activate an undetectable partition, you can try using automatic recovery at boot. If you have a problem copying the boot files to Windows 7, just call up the boot menu (F8) when restarting and use the computer troubleshooting tool.
In the case of the tenth modification of the system, it is easiest to boot from a removable medium containing the installation distribution, then enter the recovery environment and activate the restore item at boot up through several menus.
Preliminary Actions
Finally, before taking further action, it is highly recommended that you perform some additional operations. It is a matter of checking the hard drive (system partition) for errors, because if the file system is damaged or bad sectors and blocks are identified, some operations may also fail.
Again, to perform the verification, it is best to use the command line, but you need to call it when booting from the installation flash drive or disk. It uses the CHKDSK toolkit, for which you need to specify the letter of the disk to be checked (for example, chkdsk c: / x / f / r). If errors are detected, this tool will fix them yourself.
Note: the drive letter may differ from the example, therefore it is better to determine the system partition in advance by writing the diskpart and list volume commands in the command console .
BCDBoot crashes while copying boot files: how to restore bootloader
Now we move on to the basic error correction technique.
Initially, we assume that it appears when recovery is performed from the command console by executing the combination bcdboot.exe N: \ Windows, where N is the letter of the partition in which the system was installed initially (you can omit the BCDBoot applet extension when entering the main command).
So, after entering the above command, a failure message appeared when copying the Windows 10 boot files. The procedure for fixing it is as follows.
At the command console, type the commands shown in the image above. Just note that in the example the partition with the installed system is indicated by the letter “D”, but in your case the letter may be different, as well as the letter of the partition reserved by the system may also differ from that shown in the example, therefore, when choosing a disk Be extremely careful!
Restoring a reserved partition using another method
In principle, the method shown above usually resolves the problem almost always. But what if, when using it, it is again reported that a failure occurred while copying the download files? In this case, you can use another method, which is as follows.
First enter the two primary commands and determine the number of the hidden partition that you want to recover.
If you have a computer with a BIOS and an MBR disk, the partition will have a FAT32 file system and a size of about 450-500 MB. On computers with UEFI and GPT disks, the NTFS file system will be installed for the hidden partition, and the size will be 100-300 MB, which is clearly seen in the picture above.
Now, being in the command console in order, execute the following lines:
- select volume N (N - number of the hidden section);
- format fs = fat32 or format fs = ntfs (select the file system that is installed for the marked hidden partition);
- assign letter = Z (change the letter of the section);
- exit ( exit the diskpart toolkit ).
Now enter the command corresponding to starting the main copy tool, bcdboot C: \ Windows / s Z: / f ALL (C is the partition with the system files, Z is the letter just assigned to the hidden partition).
After that, get rid of the renamed section:
- diskpart
- list volume;
- select volume Z;
- remove letter = Z (delete the changed letter, so that upon restart such a section in the system does not appear);
- exit.
Upon completion of all operations, reboot the system by first setting the hard drive first in the list of devices for starting the system in BIOS / UEFI, and look at the result. In theory, the system will boot without problems.
Additional recovery tools for Windows 7 and higher
Judging by user reviews and taking into account the opinions of many experts, it makes no sense to use the solutions described above in some cases to fix a failure when copying download files, since simpler standard methods involving the use of system component check ( sfc / scannow) with subsequent restoring the bootloader by activating the Bootrec.exe tool and executing the first two combinations below (combinations after the right slash).
If their application does not give a positive result, you can perform a complete rewrite of the bootloader with the Bootrec.exe / RebuildBCD command. However, in this case, it should be borne in mind that this option is most relevant for disks with MBR, and not for GPT partitions.
Epilogue
Thus, to draw a line, it can be noted that for most cases of the manifestation of the above failure, the most appropriate is the correction method, which involves only activating the hidden partition. If for some reason it doesn’t work, use the second method with formatting and changing the drive letter. And it almost always gives a one hundred percent result. However, if automatic recovery at boot fails, all other tools may not be used at all. It is obvious!