关于BCD文件目录及自身系统对应目录与BCD文件缺失的技术咨询

Hey there! Let me clear this up for you—this discrepancy boils down to one key difference: whether your system uses Legacy BIOS or UEFI boot mode, which are two totally separate boot architectures. Here's a breakdown of what's going on:

• Boot mode dictates where BCD lives

  • For systems running on Legacy BIOS (the older boot standard), the BCD (Boot Configuration Data) is indeed stored in the System Reserved partition at the path \boot\BCD—that's the setup you found in your research.
  • But if your system uses UEFI (the modern standard for most new PCs built in the last decade), the BCD file is stored in a completely different spot: inside the EFI System Partition (ESP) at \EFI\Microsoft\Boot\BCD. The \EFI\boot\ directory you're seeing is for fallback bootloaders (like bootx64.efi), not the main BCD file.

• Why you don't see the System Reserved partition or its BCD

  • If your system was set up with UEFI from day one, it won't have a System Reserved partition. Instead, it uses the ESP—usually a small FAT32 partition—for all boot-related files.
  • Also, these system partitions are often hidden by default in File Explorer to stop users from accidentally messing with critical boot files. You can check if the ESP exists by opening Disk Management (right-click the Start menu > Disk Management) and looking for a small FAT32 partition labeled "EFI System Partition".

• How to confirm your boot mode

  • Want to be sure which mode you're using? Here's a quick way:
    1. Open Settings > System > Recovery.
    2. Click "Restart now" under Advanced startup.
    3. Once in the recovery environment, navigate to Troubleshoot > Advanced options. If you see "UEFI Firmware Settings", you're on UEFI; if that option is missing, you're running Legacy BIOS.

备注：内容来源于stack exchange，提问作者SEPEHR