The normal start up sequence for Windows 7 is:
1. Power-on self test (POST) phase.
As soon as you turn on a computer
2. Initial start up phase.
After the POST, the settings that are stored in the nonvolatile memory, such as boot order,
determine the devices that the computer can use to start an operating system.
3. Windows Boot Manager phase.
- For computers that have a single operating system, Windows Boot Manager never displays a message It wait for a few moments to allow the user to press a key to display the standard boot menu or to press F8 (Advanced Boot Options) If the user does not press a key Windows Boot Manager starts the Windows Boot Loader.
- For computers with multiple operating systems, Windows Boot Manager displays a menu of operating system choices at start up. Depending on what you choose, Windows Boot Manager will start:
- If you choose Windows Vista or Windows 7, Windows Boot Manager starts the Windows Boot Loader to open Windows.
- If you choose Earlier Version Of Windows, for example Windows XP, Windows Boot Manager starts Ntldr, which then proceeds with the hardware detection phase.
4. Windows Boot Loader phase.
The Windows Boot Loader does the following:
- Loads the operating system kernel, Ntoskrnl.exe.
- Loads the Hardware Abstraction Layer (HAL), Hal.dll
- Loads the system registry into memory.
- Scans for device drivers and loads all drivers that are configured for the boot class into memory.
- Enables paging.
- Passes control to the operating system kernel, which starts the next phase
5. Kernel loading phase.
The Windows Boot Loader is responsible for loading the Windows kernel (Ntoskrnl.exe) and the HAL into memory. Together, the kernel and the HAL initialize a group of software features that are called the Windows executive.
6. Logon phase.
The Windows subsystem starts Winlogon.exe, a system service that enables you to log on and
log off. Winlogon.exe then does the following:
- Starts the Services subsystem (Services.exe), also known as the SCM
- Starts the Local Security Authority (LSA) process (Lsass.exe).
- Parses the Ctrl+Alt+Delete key combination at the Begin Logon prompt (if the computer is part of an AD DS domain).
This sequence will vary if the computer is resuming from hibernation or if a non–Windows 7
option is selected during the Windows Boot Manager phase.