The boot process of Windows 10 begins with UEFI initializing low-level hardware and loading the Windows bootloader. The bootloader loads the kernel files and begins phase zero initialization, which sets up memory, processes, and core system components. Phase one initialization then prepares interrupt handling and loads remaining drivers before starting the SMSS process and displaying the login screen.

1. OPERATING SYSTEM
Boot process of windows 10
13004065105 Awais Ajaz
13004065107 Faizana Naeem
13004065093 Mashal Khalid
13004065074 Abdulrehman

2. UEFI
• UEFI: ”Unified Extensible Firmware Interface”:
• UEFI initializes firmware at the start.
• Firmware initializes Low level hardware
• After that it loads and execute EFI drivers
• UEFI Windows setup install into system’s non-volatile RAM(NVRAM).
• BCD stored in NVRAM
• EFI boot manager loads Winresume.EFI

3. Kernel
• The applicable kernel and HAL files are loaded
• Two files are loaded NTOSKRNL.exe HAL.dll
• VGAOFM.fon is loaded
• System registry hive is loaded
A list of Service_boot_start drivers gathered at this point e.g . storage control drive
• NTFS file system is loaded
• Boot time device drivers are now loaded
• Kernel initialization starts when windows boot loader call the kisystemstartup function of the
kernel.
• NTOSKRNL have two phases Phase 0 Phase 1

4. Phase Zero Initialization
• Interrupts disabled
• Asking HAL to initialize each processor on the system.
• Kiinitialize responsible for initialize kernel code and data structure.
• It transfer the control to InitBootprocessor.
Remove access to the specified amount of physical memory from the BCD option
BURNMEMORY.
Initializes the translation between ANSI.OEM and Unicode text
Initializes the process clock timer interrupt.
• Initializes paged and non-paged pool which is memory used by system and drivers
• InitBootprocess initializes other kernel components.
• Object manager is initialized

5. • Process manger is initialized
system idle process, the system process created during this step
• Plug and play manager initialized
• InitBootprocess initialize deferred procedure call (DFC) structures f the processor.
• transfer the control to “system idle process” if any thread call phase 1 initialization.
• Phase 1 initialization
• HAL prepares all of the system interrupt handling and the subsequently turn on the interrupt
• After interrupts have been setup
• Bootvid diver responsible for the boot screen initialized.
• After the power manager is started.
time that system has booted also record
• Remaining processors in a multiple processor system initialized
• The object manager and the kernel executive initialized
create global namespace and other directories
various objects(semaphores and mutexes)
Kernel scheduler is initialized

6. • List of drivers to start
superfetch
prefetcher
• After which file system driver asked to perform preliminary initialization
• I/O manger performs
• Configuration manager(to see system are identical in the features they support otherwise crash)
• Power manager initializing and SMSS is started
• After that winload.exe file is loaded and displays the window login screen
• After that desktop.ini file is loaded and display the desktop.