Windows Desktop Login is a virtual Smart Card technology; its authentication method can be restricted through Windows Domain Policies.

Configuring smart card requirements for domain-joined computers via Group Policy involves setting policies on a Windows Server domain controller. You can create and apply Group Policy Objects (GPOs) to control the smart card authentication settings for the domain-joined computers. Here's a step-by-step guide:

Note: You must have administrative privileges on the domain controller and the necessary permissions to create and apply GPOs.

To restrict access to Windows desktop login:

1. Access Group Policy Management Console (GPMC):
   1. Press `Win + R` to open the Run dialog box.
   2. Type `control admintools` and press Enter.
   3. Select "Windows Administrative Tools." From there, open "Group Policy Management Console."
2. Create a New Group Policy Object:
   1. In the GPMC, expand the forest and domain nodes to locate the Organizational Unit (OU) where your domain-joined computers reside.
   2. Right-click on the OU, and choose "Create a GPO in this domain, and Link it here..."
   3. Give your GPO a name that indicates its purpose, e.g., "Smart Card Authentication Policy."
3. Edit the GPO:
   1. Right-click on the newly created GPO and select "Edit" to open the Group Policy Management Editor.
4. Navigate to Smart Card Policies:
   1. In the Group Policy Management Editor, navigate to the following location:
      Computer Configuration -> Policies -> Administrative Templates -> System -> Smart Card is required for interactive logon
5. Enable Smart Card is required for interactive logon:
   1. Double-click on "Smart Card is required for interactive logon" to open its properties.
   2. Select the "Enabled" option.
   3. Click "Apply" and then "OK."
6. Close Group Policy Management Editor:
7. Link the GPO to the OU:
   1. In the GPMC, select the OU where your domain-joined computers are located.
   2. In the right pane, you should see the GPO you created. Ensure it's linked to the OU. If not, you can link it by right-clicking the OU and choosing "Link an Existing GPO..." then select your GPO.
8. Force Group Policy Update:
   1. To apply the new policy immediately, you can open a Command Prompt on the client computer and run the following command:
      gpupdate /force
9. Test Smart Card Authentication:
   1. To verify that smart card authentication is working correctly, attempt to log in to one of the domain-joined computers with a user account that has a smart card. You should be prompted to insert the smart card and provide the associated PIN.
10. Monitor and Troubleshoot:
    1. Keep an eye on the authentication process and monitor for any issues. If you encounter problems, consult the event logs and Group Policy settings for troubleshooting.

Remember that Group Policy changes can take some time to propagate across your network, so be patient if you don't see immediate results.

Additional Considerations

Remote Desktop

Configuring a Windows computer to require a smart card for interactive logon should not directly impact users accessing the system via Remote Desktop, as long as Remote Desktop authentication is handled separately. Windows allows for different authentication methods for local interactive logon and Remote Desktop access.

When you set up a smart card requirement for interactive logon as described in the previous section, it specifically applies to users attempting to log in directly at the physical computer or its console. Users attempting to connect via Remote Desktop would still need to provide the appropriate credentials (username and password or smart card authentication) when connecting remotely.

Remote Desktop authentication can be controlled independently, and you can configure it to use different authentication methods, including username/password or smart card, based on your security requirements.

To summarize, configuring a smart card requirement for interactive logon should not interfere with Remote Desktop access, but it's essential to ensure that Remote Desktop authentication settings align with your security policies and requirements.

Local Group Policy

To set up a Windows computer to require a smart card for authentication, you'll need to configure certain security settings and policies. Here's a step-by-step guide on how to do this:

Note: This process may vary slightly depending on your Windows version and edition. These instructions are written for Windows 10 and Windows 11.

1. Insert the Smart Card:
   1. Ensure that the smart card reader is connected to your computer and insert the smart card.
2. Install Smart Card Driver:
   1. If your smart card requires a driver for Windows, make sure you've installed it before proceeding.
3. Open Local Group Policy Editor:
   1. Press `Win + R` to open the Run dialog box.
   2. Type `gpedit.msc` and press Enter to open the Local Group Policy Editor.
4. Navigate to Smart Card Policies:
   1. In the Local Group Policy Editor, navigate to the following location:
      Computer Configuration -> Administrative Templates -> System -> Smart Card is required for interactive logon.
5. Enable Smart Card is required for interactive logon:
   1. Double-click on "Smart Card is required for interactive logon" to open its properties.
   2. Select the "Enabled" option.
   3. Click "Apply" and then "OK."
6. Close the Local Group Policy Editor.
7. Restart your computer to apply the changes.

After your computer restarts, it should now require a smart card for authentication. When you try to log in, you will be prompted to insert your smart card and enter the associated PIN or credentials.

Please note that the availability of Group Policy Editor and the specific policy options may vary based on your Windows edition. In some cases, you might need to use the Registry Editor to make these changes. However, be cautious when editing the registry, as incorrect changes can lead to system instability. Always back up your registry before making any changes.

Keep in mind that you need administrative privileges to configure these settings, and it's crucial to have a backup method for accessing your computer in case you encounter any issues with your smart card.

Logging for SmartCard Events

Smart card logon events in Windows are logged in the Security event log and can be identified by specific Event IDs and event descriptions. The following are the primary Windows events specific to smart card logon:

1. Event ID 4648 (A logon was attempted using explicit credentials):
   Description: This event is logged when a user attempts to log in using explicit credentials (username and smart card PIN). The "Logon Type" field in the event details will be set to 9, indicating a smart card logon attempt.
2. Event ID 4778 (A session was reconnected to a Window Station):
   Description: This event is logged when a user reconnects a remote desktop session using a smart card for authentication. The "Logon Type" field in the event details will be set to 10.
3. Event ID 4800 (The workstation was locked):
   Description: When a user locks their workstation by removing the smart card or using a keyboard shortcut, this event is logged. It indicates that the workstation was locked via a smart card-based action.
4. Event ID 4801 (The workstation was unlocked):
   Description: This event is logged when a user unlocks a workstation using a smart card. It indicates that the smart card was used to unlock the workstation.
5. Event ID 682 (Session reconnected to winstation):
   Description: In older Windows versions (prior to Windows 10 and Windows Server 2016), you might also see Event ID 682 for session reconnections with a smart card. The "Logon Type" field in the event details will be set to 10.
6. Event ID 4768 (Kerberos Authentication Service Ticket Request):
   Description: Although not specific to smart card logon, Event ID 4768 can provide information about Kerberos authentication attempts, including those involving smart cards. You can filter for specific smart card-related events using additional event data like "Service Name" or "Client Address."

These events can provide valuable information about smart card logon activities on your Windows systems. You can use tools like Event Viewer or PowerShell scripts to monitor and analyze these events for security and auditing purposes, ensuring that smart card-based authentication is functioning as intended and detecting any unauthorized access attempts.