One of the most frustrating problems to troubleshoot is when Windows does not boot and you cannot log in to Windows. To overcome these problems, you need to understand how the computer boots and be familiar with the tools available during boot up.

Every time you turn on a computer, it goes through the Power-On Self Test (POST), which initializes hardware and finds an operating system to load. The POST includes the following steps:

1. The computer does a quick power check to make sure it has enough power to supply the system.
2. When the processor receives a power good signal, the processor initializes and tests essential PC components as specified in the System ROM BIOS.
3. If a problem is found, the computer identifies the problem with a series of beeps based on the system ROM BIOS.
4. The processor then initializes the video card and starts sending information to the monitor. Next, the system initializes additional components. If a problem is discovered, it displays a message to indicate the problem.
5. The system will search for a boot device (such as a hard drive, optical disk, or USB flash drive) from which to boot.
6. The system will read the master boot record on a boot device to determine operating system boot files.

If the system is running Windows XP or Windows Server 2003, the system will go through the following steps:

1. NT loader (NTLDR) is loaded, which reads the boot.ini file to display the boot menu or to boot from a partition or volume.
2. NTDetect.com gathers information about the computer hardware as reported by the BIOS.
3. NTOSKRNL.EXE is the main part of Windows, which is responsible for various system services and process and memory management.
4. HAL.DLL implements a number of functions different ways by various hardware platforms based on processor and chipset.

If the system is running Windows Vista, Windows 7, or Windows Server 2008, the system will go through the following steps:

1. BOOTMGR is loaded, which accesses the Boot Configuration Data Store to display the boot menu or to boot from a partition or volume.
2. WINLoad is the operating system boot loader, which loads the rest of the operating system.
3. NTOSKRNL.EXE is the main part of Windows, which is responsible for various system services and process and memory management.
4. Boot-class device drivers implement a number of functions in different ways by various hardware platforms based on processor and chipset.

A master boot record (MBR) is the first 512-byte boot sector of a partitioned data storage device such as a hard disk. It is used to hold the disk’s primary partition table, contains the
code to bootstrap an operating system, which usually passes control to the volume boot record and uniquely identifies the disk media. By default, the master boot record contains the
primary partition entries in its partition table.

A volume boot record (VBR), also known as a volume boot sector or a partition boot sector, is a type of boot sector, stored in a disk volume on a hard disk, floppy disk, or similar data storage device that contains code for booting an operating system such as NTLDR and BOOTMGR.

The active partition is the partition or volume that is marked as the partition from which to boot. The active partition or volume that contains the boot file (NTLDR or BOOTMGR) is known as the system partition/volume. The partition or volume that contains the Windows operating system files (usually the Windows or WINNT folder) is called the boot partition.
It is common for the systems to have one drive and one partition/volume that makes up the partition, system partition, and boot partition.
The %SystemRoot% variable is a special system-wide environment variable found on Microsoft Windows systems. Its value is the location of the system folder, including the drive and path. By default, on a clean installation of Windows, the %SystemRoot% is C:Windows.

Understanding Boot.ini

----------------------------------------------- The Windows XP and Windows Server 2003 NTLDR will read the boot.ini file to determine which operating system to ...
Read More

Understanding BCDEdit

----------------------------------- Boot Configuration #Data (BCD) is a firmware-independent database for boot-time configuration data used by Microsoft’s Windows Boot Manager found ...
Read More

Understanding Advanced Boot Menu

----------------------------------------------- When problems occur during boot up, you may need to take some extra steps to get the computer into ...
Read More

Using the System Configuration Tool

---------------------------------------- While safe mode allows you to boot Windows when it will not boot because of a bad driver, service, ...
Read More

This lesson is a part of Monitoring and Troubleshooting Servers chapter from 98-365 Windows Server Administration Fundamentals Prep course. More lessons in this chapter are

Managing Information Technology

For most companies, an Information Technology (IT) department can be very complex. With all of the network services and applications ...
Read More

Introducing Troubleshooting Methodology

As a computer technician, a server administrator, or a network administrator, you will eventually have to deal with problems. Some ...
Read More

Booting the System

One of the most frustrating problems to troubleshoot is when Windows does not boot and you cannot log in to ...
Read More

Understanding Performance

Performance is the overall effectiveness of how data moves through the system. Of course, it is important to select the ...
Read More

Introducing Business Continuity

When a server goes down, it will most likely cause your company to lose money. If your network contains an ...
Read More

The Practice tests included in this course are:

98-365 Windows Server Administration Fundamentals Practice Test 1

Instructions for 98-365 Windows Server Administration Fundamentals Practice Test 1 This page shows the instructions for 98-365 Windows Server Administration ...
Read More

98-365 Windows Server Administration Fundamentals Practice Test 2

Instructions for 98-365 Windows Server Administration Fundamentals Practice Test 2 This page shows the instructions for 98-365 Windows Server Administration ...
Read More

98-365 Windows Server Administration Fundamentals Practice Test 5

Instructions for 98-365 Windows Server Administration Fundamentals Practice Test 5 This page shows the instructions for 98-365 Windows Server Administration ...
Read More

98-365 Windows Server Administration Fundamentals Practice Test 4

Instructions for 98-365 Windows Server Administration Fundamentals Practice Test 4 This page shows the instructions for 98-365 Windows Server Administration ...
Read More

98-365 Windows Server Administration Fundamentals Practice Test 3

Instructions for 98-365 Windows Server Administration Fundamentals Practice Test 3 This page shows the instructions for 98-365 Windows Server Administration ...
Read More