How to Rebuild BCD in Windows

A long day of searching (which is typical) for how to fix the non-booting Windows 10 installation.

Eventually I've found the following procedure, which simply just worked.
The best thing only the Option 1 (the simplest) was necessary in my case :)

1. Start Advanced Startup Options if you're using Windows 10 or Windows 8.
   Start System Recovery Options if you're using Windows 7 or Windows Vista.
2. Open Command Prompt from Advanced Startup Options or System Recovery Options menu.
3. At the prompt, type the bootrec command as shown below and then press Enter:
   

   bootrec /rebuildbcd
   

   The bootrec command will search for Windows installations not included in the BCD and then ask you if you'd like to add one or more to it.
4. You should see one of the following messages at the command line.
   
   
   1. Option 1
      

      Scanning all disks for Windows installations.
      Please wait, since this may take a while...
      Successfully scanned Windows installations.
      Total identified Windows installations: 0
      The operation completed successfully.
      

      Option 2
      

      Scanning all disks for Windows installations.
      Please wait, since this may take a while...
      Successfully scanned Windows installations.
      Total identified Windows installations: 1
      [1] C:\Windows
      Add installation to boot list? Yes/No/All:
      

   2. If you see Option 1: Move on to Step 5. This result most likely means that Windows installation data in the BCD store exists but bootrec couldn't find any additional installations of Windows on your computer to add to the BCD. That's fine; you'll just need to take a few extra steps to rebuild the BCD.
   3. If you see option 2: Enter Y or Yes to the Add installation to boot list? question, after which you should see The operation completed successfully, followed by a blinking cursor at the prompt. Finish up with Step 10 toward the bottom of the page.
   
   

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https://www.lifewire.com/how-to-rebuild-the-bcd-in-windows-2624508