This article covers details about the error ‘The requested system device cannot be found’ and a potential solution to resolve the same. But before we begin, it is important to understand some of the terms explained here,
Boot sector: Area that contains information that is necessary to load the OS
MBR: short for Master Boot Record is the first sector in the hard disk that contains info about the location of OS, so the BIOS can look for it.
BCD: short for Boot Configuration Data contains boot time configuration and this information is used by the Boot Manager
Normally, if the partition table or the boot sector is corrupt, you may not be able to boot into Windows normally. Instead, you will have to enter recovery menu or use a Windows installation media and choose to Startup repair. If this doesn’t help, you can manually troubleshoot using Bootrec.exe in the command prompt.
Using the Bootrec.exe tool, you can repair MBR, rebuild BCD or even write a new boot sector. To perform these operations are various commands such as /FixMbr, /rebuildbcd, /ScanOS etc.
/FixMbr is used to write a new MBR when the existing MBR is corrupted or damaged.
/FixBoot is used to write a new boot sector into the system partition. It is used when the boot sector is damaged
/ScanOS scans and lists all the installations that Boot Manager does not
/RebuildBCD is used to rebuild the BCD completely
/BCDEDIT is used to manage boot menu such as create new stores, modify existing ones, adding boot options etc.
While performing /BCDEDIT, some users complain about the error ‘The requested system device cannot be found’. This error normally is found when you try to perform Bootrec operations using a USB installation media. To fix this error,
- In the advanced recovery options menu, click on Command Prompt
- Type ‘diskpart’ to list all partitions and for you to identify EFI partition (Please note that EFI partition is formatted using FAT32)
- Type ‘sel vol #’ (where # is the volume number associated with this partition)
- Type ‘assign letter=x’ to assign a letter to the EFI partition; replace x with a letter of your choice
- Type ‘exit’ to exit diskpart
- Then type the following commands and hit Enter after every command
- ‘cd /d <drive letter>: \EFI\Microsoft\Boot\’
- ‘bootrec /fixboot’
- ‘ren BCD BCD.bak’
- ‘bcdboot C:\Windows /l en–gb /s <drive letter:> /f ALL’ (Using ‘/f ALL command’ will update UEFI firmware and other BIOS settings)
This solution covered should help you resolve the error ‘The requested system device cannot be found’ and rebuild BCD. However, if this method does not work, you can try reinstalling Windows from scratch. Although reinstalling Windows can be cumbersome, in worse situations, it can help.
Other than these problems, of course are data loss scenarios due to damaged boot sector or partition table. If you don’t have a proper backup in place, it can be extremely hard to deal with. Thankfully, there are data recovery programs such as Yodot Recovery to recover data from formatted or partitioned hard drives. It can also be used with GPT partitions, refer GPT partition recovery for more details.