Reparar BCD en Windows 10.

bootrec.exe /fixmbr
bootsect.exe /nt60 all /force

Entramos en la carpeta boot donde esta el bcd, en este caso es E:

attrib -h -s E:\boot\BCD
E:
cd boot
del BCD
bcdedit /createstore bcd
bcdedit.exe /store bcd /create {bootmgr} /d "Windows Boot Manager"
bcdedit.exe /store bcd /set {bootmgr} device partition=C:
bcdedit.exe /store bcd /timeout 10

bcdedit.exe /store bcd /create /d "Microsoft Windows" /application osloader
Copiamos el ID que ha creado: {c0dfc4fa-cb21-11dc-81bf-005056c00008}

Aquí tenemos que poner la unidad donde está el SO.

bcdedit.exe /store bcd /set {c0dfc4fa-cb21-11dc-81bf-005056c00008} device partition=C:
bcdedit.exe /store bcd /set {c0dfc4fa-cb21-11dc-81bf-005056c00008} osdevice partition=C:
bcdedit.exe /store bcd /set {c0dfc4fa-cb21-11dc-81bf-005056c00008} path \Windows\system32\winload.exe
bcdedit.exe /store bcd /set {c0dfc4fa-cb21-11dc-81bf-005056c00008} systemroot \Windows

bcdedit.exe /store bcd /displayorder {c0dfc4fa-cb21-11dc-81bf-005056c00008}