Would you like to learn how to configure a group policy to audit the NTLM authentication success and failure? In this tutorial, we will show you how to configure the NTLM authentication audit feature using a GPO.

• Windows 2012 R2
• Windows 2016
• Windows 2019
• Windows 10
• Windows 11

Equipment list

Here you can find the list of equipment used to create this tutorial.

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Tutorial GPO - Audit the NTLM authentication

On the domain controller, open the group policy management tool.

Windows - Group Policy management

Edit the default domain policy.

GPO - Default domain policy

On the group policy editor screen, expand the Computer configuration folder and locate the following item.

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Access the folder named Security options.

GPO - Default domain - local security options

Edit the configuration item named Network security: Restrict NTLM: Audit Incoming NTLM Traffic.

Enable the options to audit for all accounts.

GPO - Audit Incoming NTLM

Edit the configuration item named Network security: Restrict NTLM: Outgoing NTLM traffic to remote servers.

Enable the options to audit all.

GPO - Audit Outgoing NTLM

To save the group policy configuration, you need to close the Group Policy editor.

Edit the default domain controllers policy.

GPO - Default domain controllers policy

On the group policy editor screen, expand the Computer configuration folder and locate the following item.

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Access the folder named Security options.

GPO - Default domain controllers - Security Options

Edit the configuration item named Network security: Restrict NTLM: Audit NTLM authentication in this domain.

Select the option Enable all.

GPO - Audit NTLM authentication in this domain

To save the group policy configuration, you need to close the Group Policy editor.

Congratulations! You have finished the GPO creation.

Tutorial GPO - Audit NTLM logon events

After applying the GPO you need to wait for 10 or 20 minutes.

During this time the GPO will be replicated to other domain controllers.

On a remote computer, start an elevated Powershell command-line.

Windows 10 - powershell elevated

Verify the list of NTLM events that will be logged.

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Here is the command output.

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List NTLM logon events.

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Here is the command output.

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List specific NTLM events.

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Get details from the last NTLM event.

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Here is the command output.

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In our example, we configured a GPO to audit NTLM success and failure events.