Operating System Installations | CompTIA A+ 220-1002 | 1.3

In this video you will learn about general operating system installation considerations & upgrade methods pertaining to: boot methods, types of installations, partitioning, & file system types and formatting.

Boot Methods

In computing, booting is the process of starting a computer. It can be initiated by hardware such as a button press, or by a software command. After it is switched on, a computer’s central processing unit (CPU) has no software in its main memory, so some process must load software into memory before it can be executed. This may be done by hardware or firmware in the CPU, or by a separate processor in the computer system. Regardless of how this process is executed, the computer must be told how to find the software (operating system) and this is accomplished within the BIOS/UEFI boot order settings (boot sequence). A boot sequence is the order in which a computer searches for nonvolatile data storage devices containing program code to load the operating system (OS). Devices that are usually listed as boot order options in the BIOS settings are hard disks, floppy drives, optical drives, flash drives, etc. In a boot order, the computer first looks for files to load from the first place listed in the order. If the computer doesn’t find them there, it will go to the next place on the list and so on until if finds an OS to load to become operational.

BIOS Boot Order Menu

The installation process has various methods to boot a system to allow for a Windows installation file to be extracted (or an .iso file in Windows 7) such as:

  • Optical Disc:  This method is used to install Windows to an individual PC in addition to creating a master PC from which future disk images can be created.
  • Network/PXE Boot (Pre-boot Execution Environment, pronounced Pixie):  This method is used in client-server environments that boot a software assembly, retrieved from a network, on PXE-enabled clients. In layman’s terms, the OS image is stored on a server and the computer loads the image over an established network connection. This method only works if the client has a PXE-capable network interface controller (NIC).
  • Booting from USB thumb drive:  Use this method as an alternative if installing an OS from a DVD isn’t possible (such as if the computer doesn’t have a CD/DVD drive). Be mindful to change the boot order in BIOS/UEFI to allow for USB booting.
  • Booting from an HDD/SSD:  This method is where most OS will reside. Be sure to change the boot order in BIOS/UEFI so that computer knows to look here first if the OS resides here.
  • Partition on the Internal HDD or SSD:  This method is similar to booting from an internal hard drive except that a designated partition (section) of the drive has been reserved for booting an OS.

Installation Types

Unattended Installation

An unattended installation is the installation of a program without requiring the user to select options or click Next at the end of each step. Unattended installations often use a file of predefined answers so that after starting the installation, it runs to completion without further user intervention. In an attended installation, information must be provided at various points during the process.

Unattended Installation Deployment Kit

In-Place Upgrade Installation

An in-place upgrade installation is the installation of an operating system or application on a computer without removing the older version first and without saving any data beyond normal precautions. In-place installations of operating systems have a tendency to cause problems, especially if the new version is very different from the previous one. These in-place upgrades will not delete previous installations which will allow for the user to retain their apps & settings in addition to preserving their personal files as well. Also understand that Windows in-place installations only allow for 32-bit versions to upgrade to other 32-bit version and for 64-bit version to upgrade to 64-bit versions only.

In-Place Installation

Clean Install

A clean install is a completely new installation of an operating system or application on a computer. In a clean install of an OS, the hard disk is formatted and completely erased. In a clean install of an application, the older version is uninstalled first. Installing an OS on a new computer or installing an application for the first time is automatically a clean install.

Prior to initiating a clean install, check for the following:

  • Check the boot sequence order in the BIOS/UEFI to ensure the drive for installation is placed before the hard drive.
  • If installing a drive that requires additional drivers, have the drivers available on any type of removable media supported by the system.
  • If installing from a CD or DVD, a disk image (ISO or VXD), or within a virtual machine (VM), restart the system with the CD/DVD media or image file in place then press a key when prompted to boot.
Clean Installation

During a clean installation, you will be required to enter, confirm, select or provide various bits of information when prompted such as:

  • Whether you want to perform a custom installation by only selecting certain options during the clean install.
  • What edition of Windows will you be installing.
  • Your location (home, work/office, or public)…this is used to configure Windows Firewall.
  • Your network settings.
  • Partition location, partition type, & file systems.
  • Setting up administrator passwords and password hints.
  • Entering the product key to activate Windows.
  • Setting up the time, date, language, & region that your computer is physically located in.
  • Entering username & company name (optional).
  • Specifying if your computer belongs to workgroup or a domain.

Repair Installation

A repair installation is simply the process of installing a new build over an existing installation to restore working files and registry entries without losing existing programs or information. Repair installations are available in Windows 7/8/8.1/10. Be sure to make a backup copy of your data files before initiating a repair installation. Also keep in mind, an in-place installation is also known as a repair installation.

Multi-boot Installation

Multi-booting is the act of installing multiple operating systems on a single computer, and being able to choose which one to boot. The term dual-booting refers to the common configuration of specifically two operating systems. Multi-booting may require a custom boot loader. Windows 7, Windows 8/8.1, and Windows 10 all support multi-boot installations.

Multi-booting Installation

Remote Network Installation

Remote network installation is a Microsoft-supplied server that allows PXE BIOS-enabled computers to remotely execute boot environment variables. These variables are likely computers that are on a company’s (or client’s) network. Remote network installation is used to create installation images of operating systems or computer configurations, which can be used to demonstrate the installation process to users whose machines have been granted access to the remote network installation server. This eliminates the need to use a CD-ROM for installing an operating system.

Image Deployment

An image deployment is a file format used primarily with Microsoft products to allow the use of a virtual disk for startup or booting. This process is also called disk cloning. As a word of caution, do not use disk cloning to make illegal copies of Windows. Only use disk cloning software legally to make a backup copy of your installation.

Image Deployment

Recovery Partition

A recovery partition is a partition on the disk that holds the Windows Recovery Environmental (WinRE) that can repair some common boot errors or help to restore the factory settings of the OS if there is some kind of system failure. This partition has no drive letter, and you can use only Help in Disk Management. WinRE is built into Windows 10 versions for desktop editions.


PC recovery (computer recovery) is the process of recovering a PC from software or hardware-based problems and restoring it to normal working condition. It enables PC users to regain basic operations on their computers after experiencing a crash, corruption, physical/technical error or other problems that have made the PC inaccessible. To reset a PC in Windows 8 & 10:

  • Go to Settings > Recovery & click Get Started under Reset This PC.
  • After clicking Get Started, you’ll be presented 2 choices:
    • Keep My Files: For a minor reset. Allows personal files to be kept while removing apps & any settings that have been changed.
    • Remove Everything: For a major reset & removing all files. Make backup copies of personal files before selecting this option.
PC Recovery


Disk partitioning (disk slicing) is the creation of one or more regions on secondary storage, so that each region can be managed separately. These regions are called partitions. It is typically the first step of preparing a newly installed disk, before any file system is created. The disk stores the information about the partitions’ locations and sizes in an area known as the partition table that the operating system reads before any other part of the disk. Each partition then appears to the operating system as a distinct “logical” disk that uses part of the actual disk. Partitioning allows the use of different filesystems to be installed for different kinds of files. Separating user data from system data can prevent the system partition from becoming full and rendering the system unusable. Partitioning can also make backing up easier. A disadvantage is that is can be difficult to properly size partitions, resulting in having one partition with too much free space and another nearly totally allocated.

Disk Partitioning

Types of partitions include:

  • Basic: A disk that is initialized for basic storage. A basic disk contains basic volumes, such as primary partitions, extended partitions, and logical drives. Additionally, basic volumes include multi-disk volumes, such as volume sets, stripe sets, mirror sets, and stripe sets with parity.
  • Dynamic: A disk initialized for dynamic storage. A dynamic disk contains dynamic volumes, such as simple volumes, spanned volumes, striped volumes, mirrored volumes, and RAID 5 volumes. With dynamic storage, disk and volume management can be performed without the need to restart Windows.
  • Primary: Allows for the creation of up to four primary partitions on a basic disk. Each hard disk must have at least one primary partition where you can create a logical volume. You can set only one partition as an active partition. Primary partitions are assigned drive letters.
  • Extended: When the need for more partitions on a basic disk exist, you can create an extended partition to meet your extra disk partition requirements. You can create logical drives in the extended partition to organize data files.
  • Logical: Use logical drives to organize data files when there are not enough primary partitions to meet storage requirements. Unlike primary and extended partitions, logical drives are not assigned any drive letters. Logical partitions can be created by any number of logical drives within the extended partitions.
  • GPT: GPT partitioning creates one or more primary partitions.  There are no extended partitions or logical drives on a GPT drive; each partition can be assigned a drive letter.  However, only one partition can be active.

File System Types/Formatting

In computing, a file system controls how data is stored and retrieved. Without a file system, data placed in a storage medium would be one large body of data with no way to tell where one piece of data stops and the next begins. By separating the data into pieces and giving each piece a name, the data is easily isolated and identified. As mentioned in the previous section, Windows supports 3 different file systems for hard drives & USB flash drives: FAT32, NTFS, & exFAT.

File System Format Comparison

Swap Partition

A swap partition serves as overflow space for RAM. If the RAM fills up completely, additional applications will run off the swap partition rather than the RAM. This feature is called virtual memory in Windows and swap space in Linux. This feature is specially formatted to be used only as extra RAM and not additional storage space.

Quick Formatting vs. Full Formatting

Quick formatting & full formatting is in reference to erasing a hard drive or some other storage device.

  • Quick Formatting: Allows for the overwriting of files on a drive but it does not fully erase the files. With the proper software, the old files can be recovered. In Windows, FAT & NTFS formats allow for quick formatting.
  • Full Formatting: Erases any files from the entire disk structure, changes (or maintains) the file system & checks the disk for bad sectors. Full formats take significantly longer than a quick format. In Windows, FAT & NTFS formats allow for full formatting.

Loading Alternative Drivers

There may be times when Windows does not detect a hard drive during installation so an alternate third-party driver must be installed to complete the installation. This will typically happen when dealing with third-party SATA or RAID onboard or add-on card host adapters that are used in Windows 7/8/8.1/10. Device drivers are added using the same screen that is used for partitioning and clicking Load Driver. Device drivers can be installed from CD, DVD, or USB flash drive.

Load Driver

Workgroup vs. Domain Setup

During the installation process, you will be asked to connect your computer to either a workgroup or a domain. The differences are as follows:

  • Workgroup: Computers running Microsoft OS in home networks & small offices may share files, printers, or internet connection.
  • Domain Controller: A server computer that responds to security authentication requests within a computer network domain. It is a network server used in primarily large networks like workplaces or schools that is responsible for allowing host access to domain resources. It authenticates users, stores user account information & enforces security policy for a domain.

Time/Date/Language/Region Settings

New installations of Windows will prompt for the user to input the time, date, language & region that the user will be using the computer. If a user is performing a repair or in-place upgrade, the settings from the previous install will be utilized.

Driver Installation, Software, & Windows Updates

After you have installed a version of Windows, the next thing you should do is update the system. The easiest way to perform an update is to set up Windows Update for automatic updates.

Factory Recovery Partition

Most modern computers with OEM (original equipment manufacturer) pre-installed Windows come with a factory recovery partition (also called a system restoration disc which is a disk partition containing a special recovery image of the Windows installation). This partition allows users to restore Windows 10 to its original state like when it was shipped from the factory. Usually, you will be prompted to burn a restore image to one or more CDs/DVDs or a USB flash drive. Be mindful that may need a Windows product key or your system’s serial number to run the recovery disc program.

Properly Formatted Boot Drive with Correct Partition/Format

To properly format a boot drive with correct partitions, use a new drive or a clean formatted drive using the disk setup utility. You can use old drives, but they should be completely formatted of old files prior to.

Prerequisites/Hardware Compatibility


When performing a clean install, make sure your hardware meets the prerequisites for working with the software which is usually a minimal amount of RAM and a certain level of processing power. Current requirements for Windows 10:

  • Processor:  1GHz or faster processor or System on a Chip (SoC)
  • RAM:  1GB for 32-bit OS or 2GB for 64-bit OS
  • Hard drive space:  16GB for 32-bit OS or 32GB for 64-bit OS
  • Graphics card:  DirectX 9 or later with WDDM 1.0 driver
  • Display:  800×600
  • Internet Connection:  Internet connectivity to perform updates

Hardware & Application Compatibility

The easiest way to check for compatibility with a Windows OS is to go straight to Microsoft’s website.  Microsoft has what is called the Hardware Compatibility List (HCL), also known as Windows Compatibility Product List.  The HCL provides info about manufactures and drivers that can or cannot be used with Windows.  The Hardware Compatibility Checker matches compatible products for Windows and macOS.

To check to see if a certain program works with a certain OS, you can use the Compatibility Troubleshooter tool. In Windows 10:

  • Right-click the program then select Properties > Compatibility > Run This Program in Compatibility Mode then select the previously used OS.
  • Alternate option in Windows 10:
    • In search bar type Run Programs then select Run Programs Created for Previous Versions of Windows.