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Fix Boot Error 0xC000000F (An Error Occured While Attempting to Read the Boot Configuration Data)

Contents

1. Symptoms of the problem

When computer is powered up, an error message "Status: 0xc000000f
Info: An error occured while attempting to read the boot configuration data" appears:
Boot Error 0xC000000F (Required Device is Inaccessible)

2. Normal boot sequence

The rest of this article refers to Windows 7, but all information below applies to Windows Vista and Windows 8 as well.
Normally Windows 7 boots as shown below:
Normal boot sequence of Windows 7
  1. BIOS loads 1st sector from HDD (Master Boot Record), verifies 55 AA signature and transfers control to Master Boot Record.
  2. Master Boot Record scans partition table for active partition, then it loads 1st sector from active partition, verifies 55 AA signature, and transfers control to Boot Sector.
  3. Boot Sector loads 15 additional sectors from the beginning of disk (Volume Boot Record) and transfers control to first additional sector of VBR.
  4. Volume Boot Record loads BOOTMGR file from root directory of boot partition into the memory and transfers control to it.
  5. BOOTMGR loads Boot\BCD registry hive and displays boot menu. BOOTMGR is able to run memory test and set safe mode boot flag per explicit user request. But normally, it loads winload.exe when computer boots normally (cold startup) or winresume.exe (when computer resumes from hibernation).
  6. Winload.exe opens SYSTEM registry hive, gets list of drivers, loads NTOSKRNL.exe, loads drivers (*.SYS files) and transfers control to NTOSKRNL.exe.
  7. Winresume.exe loads memory dump from hiberfil.sys and transfers control to it.

3. Defect in the boot sequence which leads to 'status 0xC000000F' boot error

Defect in the boot sequence which is a reason for 'status 0xC000000F' error is shown below:
Reason for status 0xC000000F
  1. BIOS loads 1st sector from HDD (Master Boot Record), verifies 55 AA signature and transfers control to Master Boot Record.
  2. Master Boot Record scans partition table for active partition. There is one active partition, so Master Boot Record loads 1st sector from active partition (Boot Sector), and transfers control to it.
  3. Boot Sector loads 15 additional sectors from the beginning of disk (Volume Boot Record) and transfers control to first additional sector of VBR.
  4. Volume Boot Record loads BOOTMGR file from root directory of boot partition into the memory and transfers control to it.
  5. BOOTMGR tries to load Boot\BCD registry hive, but BCD is corrupt or misconfigured.
  6. The rest of usual boot events does not happen.

4. How to fix status 0xC000000F

1) Download EBCD and burn it to CD/DVD according to the instructions, then set up your BIOS to boot from CD. You need full EBCD version to actually write changes to the disk, but it's recommended to try demo version first to make sure  there are no hardware incompatibilities.
2) Boot EBCD:
Fix BCD status 0xC000000F with EBCD - Main Menu
3) Run File Manager from the main menu:
Fix BCD status 0xC000000F with EBCD - File Manager Started
4) Press Alt+F1 and choose your boot partition from the menu. In Windows 7 and Windows 8 boot partition has size about 100MB in size and "System Reserved" volume label. In Windows Vista separate boot partition does not exist, computer boots from system disk where Windows OS files are installed (use UP and DOWN arrow keys and ENTER to navigate the menu):
Fix BCD status 0xC000000F with EBCD - Choosing Windows 7 boot partition
5) Press TAB to switch input focus to the left panel, and go to Boot folder (using arrow keys UP and DOWN and ENTER to enter the folder):
Fix BCD status 0xC000000F with EBCD - Entering Boot Folder on the Boot Partition
6) List of files should appear on the left panel. BCD file should be in the list, BCD.LOG, BCD.LOG1 and BCD.LOG2 may also appear in the list. Navigate to that files using arrow keys, then select them INSERT key:
Fix BCD status 0xC000000F with EBCD - Selection of BCD-related Files For Backup
7) After selection:
Fix BCD status 0xC000000F with EBCD - BCD-related Files are Ready to be Renamed
8) Press F6. File rename dialog will pop up:
Fix BCD status 0xC000000F with EBCD - File Rename Dialog
9) Type BCD_OLD.* on keyboard and press ENTER:
Fix BCD status 0xC000000F with EBCD - About to Rename BCD-related Files for Backup
10) Make sure BCD files were renamed successfully to BCD_OLD files, then press F10 and ENTER to exit EBCD File Manager:
Fix BCD status 0xC000000F with EBCD - Exiting EBCD File Manager
11) Choose Mount & Boot Center in the main menu:
Fix BCD status 0xC000000F with EBCD - Choosing Mount and Boot Center in the main menu
12) Wait:
Fix BCD status 0xC000000F with EBCD - Waiting for EBCD Mount and Boot Center to start
13) Enable checkbox (checkboxes) on the intersection of the bootloader and operating system (operating systems) it should load:
Fix BCD status 0xC000000F with EBCD - Fixing Boot Error in EBCD Mount and Boot Center
14) Mount & Boot Center should look like below. Press OK to commit changes (BCD registry hive and corresponding log will be created from scratch at this point):
Fix BCD status 0xC000000F with EBCD - Saving Updated BCD Registry Changes to the Disk
15) "Status 0xC000000F" boot problem should be fixed now. Choose 'Reboot' in the EBCD main menu:
Fix BCD status 0xC000000F with EBCD - Status 0xC000000F problem is fixed, rebooting
Please note: Because BCD (Boot Configuration Data) was recreated from scratch, you may need to adjust boot timeout, menu order etc from within Windows when it boots successfully.

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