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Boot Process (detailed)

The Windows boot process is quite complicated, especially in the newer versions. Here I provide a highly detailed, step-by-step description that should be invaluable for trouble-shooting purposes. This was written because many exisitng web pages gloss over important details or are just plain wrong. I spent weeks recovering a system from a fouled-up hard drive, so the descriptions are based not only on research from various sources, but meticulous real-world experience.

I will be discussing the boot process of Windows Vista/7, but it should be noted Windows 2000 and XP are very similar. There will also be some similarities for Windows 9x, however there will be many more differences and won't explained in detail. I will be discussing the various stages, telling you mainly their names and purposes. I don't have the time (or web space!) to decribe all the parts in detail. Hopefully it will give you a solid overview of what is happening and thus allow you to find more details if needed.
Originally I wanted to provide a one-page overview, but it turned into a huge web page.  So now I've broken it into seperate pages (some are incomplete):
  • Phase 1 - BIOS
  • Phase 2 - El Torito
  • Phase 3 - Master Boot Record (MBR) of Hard Disk
  • Phase 4 - Boot Sector of File System (VBR)
  • Phase 5 - NTLDR or BOOTMGR
  • Phase 6 - Winload & System Registry
  • Phase 7 - Device Drivers & Kernel
  • Phase 8 - SMSS, Services & LSASS
  • Phase 9 - CSRSS & Software Registry
  • Phase 10 - User Registry and Shell
Note that phases 2 or 3 may be skipped, depending on the type of storage device used to boot the system.

© H2Obsession, 2014