Windows 10: understanding bootrec fixmbr, fixboot, rebuildbcd.

I've been trying to find an explanation of what the mbr, boot record and bcd store are.I've seen info like this ..https://support.microsoft.com/en-us/topic/use-bootrec-exe-in-the-windows-re-to-troubleshoot-startup-issues-902ebb04-daa3-4f90-579f-0fbf51f7dd5dand I understand I think that they are located in the system partition. However I've been unable to find an explanation of how the windows boot process uses these. I've done searches but they just get swamped by the old info on MBR drives and "repair your boot" sites.

:)

 

Access denied on bootrec /fixboot

These are the commands and how to run them. No reason you should get Access denied.
Fix the MBR – Guide for Windows 10, 11, XP, Vista, 7, 8

 

Bootrec /fixboot - Access Denied Error

I am trying to repair Windows 10 on an Acer laptop.

The USB windows repair boot disc wont repair it automatically so went to the Troubleshoot menu and the command line tools where your articles suggest I try the following commands.

Bootrec /fixmbr, This seems to work.

Bootrec /fixboot This come back with an "Access Denied" message

Bootrec /rebuildbcd This finds the windows installation and asks to add to the boot list, which I say Yes and then it says it cannot find the path specified.

Is there any chance of a fix to this issue. I note many users have a problem with doing this.

 

Error Code 0xc000000e “element not found” bootrec /fixboot

Error Code 0xc000000e

attempting Win10 Recovery from USB

Trying to fix corrupted “C” drive yet the recovery command prompt stars at “x:\Sources>”

“element not found” bootrec /fixboot

How to select the correct disk and make the Windows active and run the commands again?

If the commands are run from “x:\Sources>” or "x:\Windows\System32" it gives the same error.

here is what's been tried: [FIX] Windows 10 Master Boot Record Is Corrupted

• BOOTREC /FIXMBR (ok)
  
  
• BOOTREC /FIXBOOT (“element not found”)
  
  
• BOOTREC /REBUILDBCD (have not made it to this step)