Introduction
In a modern organization, employees rely on centralized systems every day to access computers, applications, files, and other business resources. Behind these routine activities, Active Directory helps determine who can authenticate, what they can access, and how security events are controlled and recorded.
In this hands-on exercise, I strengthened an Active Directory environment by applying targeted security controls through Group Policy. I restricted NTLM authentication, enabled auditing for user account management within the Sydney organizational unit, and configured logon restrictions for members of a security group.
These configurations demonstrate how organizations can reduce legacy authentication risks, improve visibility into account-related changes, and enforce tighter access controls. The exercise provided practical experience translating security requirements into Windows Server and Active Directory policies that support a more secure and auditable enterprise environment.
Overview
In this exercise, you configure settings related to security including disabling NTLM authentication for domain accounts, auditing account management activity, and denying log on as a service for members of a security group.
This exercise should take approximately 10 minutes to complete.
Restrict NTLM Authentication
In this task, you restrict NTLM authentication. To complete this task, perform the following steps in TAILWIND-DC1:
1.From the Tools menu of the Server Manager console, open the Group Policy Management console.
2.In the Group Policy Management console, expand the tailwindtraders.internal forest, the Domains folder, and the tailwindtraders.internal domain. Then expand Group Policy Objects.
3.Right-click Default Domain Controller Policy and click Edit.
4.Navigate to Computer Configuration\Policies\Windows Settings\Security Settings\Local Policies\Security Options.
5.Select and double-click Network security: Restrict NTLM: NTLM authentication in this domain.
6.Click the Define this policy setting check box.
7.Select the value Deny all and click OK.
8.Click Yes in the Confirm Setting Change dialog box.
9.Close the Group Policy Management Editor.
Audit User Account Management in Sydney
In this task, you enable auditing of User Account Management in the Sydney OU. To complete this task, perform the following steps in TAILWIND-DC1:
1.From the Tools menu of the Server Manager console, choose Group Policy Management Console.
2.In the Group Policy Management Console, expand the Tailwindtraders.internal domain.
3.Navigate to the Sydney OU, right-click and select Create a GPO in this domain, and link it here….
4.Name the new GPO SydneyOUPolicy.
5.Click OK
6.Right-click SydneyOUPolicy and select Edit.
7.Browse to Computer Configuration\Policies\Windows Settings\Security Settings\Advanced Audit Policy Configuration\Audit Policies\Account Management.
8.Select and double-click Audit User account management.
9.Click the Configure the following audit events check box.
10.Select the Success and Failure values and click OK.
11.Close the Group Policy Management Editor
Deny Log On As a Service
In this task, you configure the Deny Log On As A Service security option. To complete this task, perform the following steps in TAILWIND-DC1:
1.From the Tools menu of the Server Manager console, open the Group Policy Management console.
2.Expand Tailwindtraders.internal domain.
3.Browse to the Sydney OU and right-click SydneyOUPolicy. Select Edit.
4.Browse to Computer Configuration\Policies\Windows Settings\Security Settings\Local Policies\User Rights Assignment.
5.Select and double-click the Deny Log on as a service policy.
6.Select the Define this policy setting.
7.Click Add User or Group.
8.Click Browse, click Advanced, and then click Find now.
9.Select Sydney Administrators group.
10.Click OK until dialogue boxes are closed (it may require four or five acknowledgements).
Conclusion
This exercise demonstrated how Group Policy can be used to implement practical security controls across an Active Directory environment. By restricting NTLM authentication, I strengthened authentication security and reduced reliance on legacy protocols. Enabling successful and failed user account management auditing improved visibility into account-related activity within the Sydney OU. Finally, configuring Deny log on as a service for the Sydney Administrators group reinforced least-privilege access and reduced unnecessary service logon exposure.
Overall, the exercise provided valuable hands-on experience in Active Directory security hardening, auditing, authentication control, and Group Policy administration, these are key skills for managing secure Windows Server environments.
