15 Windows Interview Questions and Answers

Windows remains one of the most widely used operating systems in both personal and professional environments. Its versatility, user-friendly interface, and extensive support for a variety of applications make it a staple in many organizations. Understanding Windows’ architecture, features, and troubleshooting techniques is crucial for anyone looking to excel in roles that require system administration, IT support, or software development.

This article offers a curated selection of interview questions designed to test and enhance your knowledge of Windows. By working through these questions, you will gain a deeper understanding of key concepts and be better prepared to demonstrate your expertise in any technical interview setting.

Windows Interview Questions and Answers

1. Explain the purpose and functionality of the Windows Registry.

The Windows Registry is a hierarchical database that contains essential data for the operating system and applications. It is divided into keys and subkeys, each storing specific information. The Registry provides a centralized location for configuration settings, allowing for easier management and consistency across the system.

The Registry is organized into five main root keys:

• HKEY_CLASSES_ROOT (HKCR): Stores information about registered applications, including file associations and OLE object class IDs.
• HKEY_CURRENT_USER (HKCU): Contains user-specific settings for the currently logged-in user.
• HKEY_LOCAL_MACHINE (HKLM): Stores settings specific to the local computer, including hardware and software configurations.
• HKEY_USERS (HKU): Contains user-specific settings for all user profiles on the computer.
• HKEY_CURRENT_CONFIG (HKCC): Stores information about the current hardware profile used by the computer at startup.

The Registry allows for efficient access and modification of configuration settings, which can be done using tools like the Registry Editor (regedit.exe). It also supports remote access, enabling administrators to manage settings on multiple computers within a network.

2. Write a PowerShell script to list all running processes.

To list all running processes in Windows using PowerShell, you can use the Get-Process cmdlet. This retrieves information about the processes running on a local or remote computer. Here is a simple PowerShell script to list all running processes:

Get-Process

This command will display a list of all running processes along with details such as the process name, process ID (PID), CPU usage, and memory usage.

3. Describe how Group Policy works and provide an example of its application.

Group Policy applies policies to users and computers based on their membership in Active Directory containers such as sites, domains, and organizational units (OUs). These policies are defined in Group Policy Objects (GPOs), which are linked to these containers. When a user logs in or a computer starts up, the Group Policy client retrieves the relevant GPOs from the domain controller and applies the settings.

An example of Group Policy application is configuring password policies for users in an organization. An administrator can create a GPO that enforces password complexity requirements, such as a minimum length and the inclusion of special characters. This GPO can then be linked to the domain or a specific OU containing user accounts. When users within the scope of the GPO attempt to change their passwords, the system will enforce the defined complexity requirements.

4. What are the differences between NTFS and FAT32 file systems?

NTFS (New Technology File System) and FAT32 (File Allocation Table 32) are two different file systems used by Windows operating systems. Here are the key differences between them:

• File Size Limits: NTFS supports very large files, up to 16 TB on Windows 10, whereas FAT32 has a maximum file size limit of 4 GB.
• Volume Size Limits: NTFS can handle volumes up to 256 TB, while FAT32 is limited to 32 GB volumes in Windows.
• Security: NTFS provides file-level security with permissions and encryption, which FAT32 does not support.
• Reliability: NTFS includes features like transaction logging and recovery, which help in maintaining data integrity. FAT32 lacks these features.
• Compatibility: FAT32 is more compatible with older operating systems and non-Windows devices, such as gaming consoles and some media players. NTFS is primarily used in modern Windows environments.
• Performance: NTFS generally offers better performance, especially on larger volumes, due to its advanced data structures and indexing.

5. Write a PowerShell script to check disk space usage on all drives.

To check disk space usage on all drives using PowerShell, you can use the Get-PSDrive cmdlet, which retrieves information about the drives on the system. You can then filter the results to include only the file system drives and display their used and free space.

Get-PSDrive -PSProvider FileSystem | ForEach-Object {
    $usedSpace = ($_.Used / 1GB)
    $freeSpace = ($_.Free / 1GB)
    $totalSpace = ($_.Used + $_.Free) / 1GB
    [PSCustomObject]@{
        Drive = $_.Name
        UsedSpaceGB = [math]::Round($usedSpace, 2)
        FreeSpaceGB = [math]::Round($freeSpace, 2)
        TotalSpaceGB = [math]::Round($totalSpace, 2)
    }
} | Format-Table -AutoSize

6. Describe the process of setting up a Windows Server as a Domain Controller.

Setting up a Windows Server as a Domain Controller involves several steps:

1. Install the Windows Server Operating System: Ensure that the server is running a supported version of Windows Server.
2. Configure the Server’s Network Settings: Assign a static IP address to the server to ensure consistent network communication.
3. Install the Active Directory Domain Services (AD DS) Role: Use the Server Manager to add the AD DS role to the server.
4. Promote the Server to a Domain Controller: After installing the AD DS role, use the Active Directory Domain Services Configuration Wizard to promote the server to a Domain Controller. This involves creating a new domain or adding the server to an existing domain.
5. Configure DNS Settings: Ensure that the server is configured to use itself as the primary DNS server.
6. Verify the Installation: After the server has been promoted to a Domain Controller, verify that the installation was successful by checking the Active Directory Users and Computers console and ensuring that the server is listed as a Domain Controller.

7. Write a PowerShell script to create a new user account and add it to a specific group.

To create a new user account and add it to a specific group in Windows using PowerShell, you can use the following script:

# Define the username, password, and group
$username = "newuser"
$password = ConvertTo-SecureString "P@ssw0rd" -AsPlainText -Force
$group = "Users"

# Create the new user account
New-LocalUser -Name $username -Password $password -FullName "New User" -Description "A new user account"

# Add the new user to the specified group
Add-LocalGroupMember -Group $group -Member $username

8. Explain the concept of Windows Services and how to manage them.

Windows Services are long-running executable applications that run in their own Windows sessions. They can be automatically started when the computer boots, can be paused and restarted, and do not show any user interface. These services are ideal for running background tasks that do not require user interaction.

To manage Windows Services, you can use several tools:

• Services Management Console (services.msc): This graphical tool allows you to start, stop, pause, resume, and configure services. You can access it by typing “services.msc” in the Run dialog (Win + R).
• Task Manager: You can manage services through the Services tab in Task Manager. Right-click on the taskbar and select Task Manager, then navigate to the Services tab.
• Command Line (sc.exe): The sc command allows you to create, start, stop, query, and delete services from the command line. For example, to start a service, you can use:

  sc start ServiceName

• PowerShell: PowerShell provides cmdlets for managing services, such as Get-Service, Start-Service, Stop-Service, and Restart-Service. For example, to stop a service, you can use:

  Stop-Service -Name "ServiceName"

9. Write a PowerShell script to retrieve event logs from the Event Viewer.

To retrieve event logs from the Event Viewer using PowerShell, you can use the Get-EventLog cmdlet. This cmdlet allows you to specify the log name and other parameters to filter the events you are interested in.

Example:

# Retrieve the last 10 entries from the System log
Get-EventLog -LogName System -Newest 10

# Retrieve all entries from the Application log where the event ID is 1000
Get-EventLog -LogName Application -InstanceId 1000

10. How do you implement BitLocker encryption on a system?

BitLocker is a full-disk encryption feature included with Windows operating systems, designed to protect data by providing encryption for entire volumes. Implementing BitLocker encryption involves several steps:

• Ensure that the system meets the hardware requirements, such as having a Trusted Platform Module (TPM) version 1.2 or later.
• Open the BitLocker Drive Encryption control panel.
• Select the drive you want to encrypt and click “Turn on BitLocker.”
• Choose how you want to unlock your drive at startup, such as using a PIN, password, or USB key.
• Select where you want to save the recovery key, which can be used to access your drive if you forget your password or lose your USB key.
• Choose whether to encrypt the entire drive or just the used disk space.
• Start the encryption process, which may take some time depending on the size of the drive and the amount of data.

11. Write a PowerShell script to monitor CPU usage and alert if it exceeds a threshold.

To monitor CPU usage and alert if it exceeds a threshold, you can use the following PowerShell script. This script continuously checks the CPU usage and sends an alert if it goes beyond the specified limit.

$threshold = 80
while ($true) {
    $cpu = Get-WmiObject win32_processor | Measure-Object -Property LoadPercentage -Average | Select-Object -ExpandProperty Average
    if ($cpu -gt $threshold) {
        Write-Host "Alert: CPU usage is above $threshold%. Current usage: $cpu%"
    }
    Start-Sleep -Seconds 5
}

12. Explain the role of Windows Update and how to manage updates in an enterprise environment.

Windows Update automates the process of downloading and installing software updates. These updates can include patches for security vulnerabilities, enhancements to system performance, and new features. The primary role of Windows Update is to ensure that systems remain secure and up-to-date with the latest software improvements.

In an enterprise environment, managing updates is important to maintain the security and efficiency of multiple systems. This can be achieved through several methods:

• Windows Server Update Services (WSUS): WSUS allows administrators to manage the distribution of updates released through Microsoft Update to computers in a corporate environment. It provides control over which updates are deployed and when.
• Group Policy: Group Policy settings can be configured to control how and when updates are applied. This includes scheduling update installations, specifying update sources, and enforcing update policies.
• System Center Configuration Manager (SCCM): SCCM provides a comprehensive solution for change and configuration management. It allows for detailed control over the deployment of updates, including compliance reporting and automated workflows.
• Windows Update for Business: This service provides additional controls for managing update deployments, such as deferring updates and setting maintenance windows, without the need for additional infrastructure.

13. How would you secure a Windows Server against common threats?

Securing a Windows Server involves implementing a series of best practices and security measures to protect the system from unauthorized access, malware, and other vulnerabilities. Here are some key strategies:

• Regular Updates and Patching: Ensure that the Windows Server is always up-to-date with the latest security patches and updates.
• User Account Management: Implement the principle of least privilege by granting users only the permissions they need to perform their tasks. Use strong, complex passwords and enforce regular password changes.
• Firewall Configuration: Configure the Windows Firewall to block unnecessary ports and services. Only allow traffic that is essential for the server’s operation.
• Antivirus and Anti-malware Software: Install and regularly update antivirus and anti-malware software to detect and remove malicious software.
• Security Policies: Implement Group Policies to enforce security settings across the server. This includes password policies, account lockout policies, and audit policies.
• Network Security: Use Virtual Private Networks (VPNs) for remote access and ensure that all network communications are encrypted.
• Backup and Recovery: Regularly back up critical data and have a disaster recovery plan in place. Ensure that backups are stored securely and tested periodically.
• Monitoring and Logging: Enable logging and monitoring to detect and respond to suspicious activities. Use tools like Windows Event Viewer and third-party monitoring solutions.
• Disable Unnecessary Services: Disable any services that are not required for the server’s operation to reduce the attack surface.
• Security Tools: Utilize built-in security tools such as Windows Defender, BitLocker for disk encryption, and Windows Security Baselines to enhance the server’s security posture.

14. Explain the importance of Windows Event Logging and how to utilize it.

Windows Event Logging is a built-in feature that records various types of events, such as system errors, application failures, and security breaches. These logs are stored in the Event Viewer, which categorizes them into different types: Application, Security, System, and more.

The importance of Windows Event Logging includes:

• System Monitoring: Helps in monitoring the health and performance of the system by logging hardware and software events.
• Security Auditing: Records security-related events, such as login attempts and access to sensitive files, aiding in the detection of unauthorized activities.
• Troubleshooting: Provides detailed information about errors and warnings, making it easier to diagnose and resolve issues.
• Compliance: Assists in meeting regulatory requirements by maintaining logs of critical events and activities.

To utilize Windows Event Logging, administrators can access the Event Viewer by typing “Event Viewer” in the Windows search bar. Once opened, they can navigate through different log categories, filter events based on specific criteria, and even set up custom views for more efficient monitoring.

15. Explain the backup and restore procedures in Windows.

Backup and restore procedures in Windows are essential for ensuring data integrity and availability. Windows provides several built-in tools to facilitate these processes, including File History, Backup and Restore (Windows 7), and System Image Backup.

File History is designed to continuously back up personal files stored in libraries, desktop, favorites, and contacts. It allows users to restore previous versions of files in case of accidental deletion or modification.

Backup and Restore (Windows 7) is a legacy tool that allows users to create backups of files and system images. It provides options for scheduling regular backups and restoring files or entire system images.

System Image Backup creates a complete image of the entire system, including the operating system, installed programs, and user data. This image can be used to restore the system to a previous state in case of a failure.

To perform a backup using File History:

• Go to Settings > Update & Security > Backup.
• Select “Add a drive” and choose an external drive or network location.
• Turn on File History to start backing up files.

To perform a backup using Backup and Restore (Windows 7):

• Go to Control Panel > System and Security > Backup and Restore (Windows 7).
• Select “Set up backup” and choose a backup destination.
• Follow the wizard to select files and schedule the backup.

To create a System Image Backup:

• Go to Control Panel > System and Security > Backup and Restore (Windows 7).
• Select “Create a system image” from the left pane.
• Choose a destination to save the system image and follow the wizard.

To restore files or system images, users can access the respective tools and follow the prompts to select the backup and restore the data.