OS
BOOT FILES
DOS
Boot up Sequence
IO.SYS – A binary file that provides basic
input/output interface between the ROM BIOS and the Hardware
MSDOS.SYS – A binary file considered to be
the core of the DOS operating system
CONFIG.SYS – A text file used to load drivers
and memory managers and also use to configure the system to the user’s
needs
COMMAND.COM – DOS user interface loads the
command prompt which interprets DOS commands
AUTOEXEC.BAT – A text file that contains setting
up display settings, environment variables and routines
Win 9X Boot up Sequence
IO.SYS - I/O files use to communicate with the BIOS
MSDOS.SYS - Loads OS into memory (Also use to configure
boot files in windows 9x)
SYSTEM.DAT and USER.DAT - system and user settings
(REGEDIT)
CONFIG.SYS - loads device drivers for backwards compatibility
AUTOEXEC.BAT - sets system environment use for backwards
compatibility
WIN.COM - Initiates the Windows 9x protected load
phase
SYSTEM.INI - use to configure 16-bit windows drivers
and critical files
WIN.INI- sets 16-bit windows environment
VxD - loads windows virtual device drivers
Windows 2000/XP/NT Key Boot Files
NTLDR – Found in the MBR this file boots up
the Windows 2K/XP operating system
BOOT.INI - is text file that lists the available
OS found and tells the NTLDR where to find boot partition
BOOTSECT.DOS – Locates the IO.SYS file so you
can start another OS in a dual boot environment
NTDETECT.COM – Loads into protected mode and
detects the installed hardware on your system
NTBOOTDD.SYS - On a system with a SCSI boot device,
this file is used to recognize and load the SCSI boot partition.
NTOSKRNL.EXE- Windows 2000 Core Files
WIN.COM - Windows 2000 command file
HAL.DLL - Hardware Abstraction layer of Windows 2K/XP
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