Always On VPN Trusted Network Detection

Always On VPN Trusted Network DetectionWhen deploying Windows 10 Always On VPN, administrators can configure Trusted Network Detection (TND) which enables clients to detect when they are on the internal network. With this option set, the client will only automatically establish a VPN connection when it is outside the trusted network. Trusted network detection can be configured on both device tunnel and user tunnel connections.

TND Operation

When trusted network detection is configured, the VPN client will evaluate the DNS suffix assigned to all physical (non-virtual or tunnel) adapters that are active. If any of them match the administrator-defined trusted network setting, the client is determined to be on the internal network and the VPN connection will not connect. If the DNS suffix is not present on any of these adapters, the client is determined to be outside the internal network and the VPN connection will establish automatically.

TND Configuration

Trusted network detection is defined in the Intune UI or in ProfileXML as a string that matches the DNS suffix assigned to clients on the internal network. In this example, the DNS suffix on the internal network is lab.richardhicks.net.

Always On VPN Trusted Network Detection

Note: Your organization might have more than one DNS suffix. Ensure that the trusted network detection configuration includes all DNS suffixes in use in the environment to ensure reliable operation.

Intune

Follow the steps below to configured trusted network detection in Microsoft Intune.

  1. Open the Intune management portal (https://devicemanagement.microsoft.com/).
  2. Navigate to Devices > Configuration Profiles > [Profile Name] > Properties > Settings.
  3. Click on Trusted Network Detection.
  4. Enter the DNS suffix(es) used on the internal network.

Always On VPN Trusted Network Detection

ProfileXML

To define Trusted Network Detection in ProfileXML, add the TrustedNetworkDetection element as follows.

Always On VPN Trusted Network Detection

Caveats

In some instances, an Always On VPN client connection may persist, even if the client is connected to the internal network. A common scenario is when a client device connects to a Wi-Fi network that is not connected to the corporate network (for example guest Wi-Fi), then connects to the internal network with Ethernet via a docking station. If the Wi-Fi connection is still available, the Always On VPN connection will persist, even though the machine is connected to the internal network. This is expected and by design.

Workaround

To address this specific scenario, administrators can implement changes via group policy to the way Windows handles multiple connections to the same network. For example, beginning with Windows 10 1709, group policy can be configured to ensure that Windows 10 clients prefer wired Ethernet network connections over Wi-Fi, and to ensure that Wi-Fi connections disconnect when an Ethernet connection is detected.

GPO Configuration

Open the Group Policy management console (gpmc.msc) and perform the following steps to create the required group policy objects.

  1. Create a new Group Policy Object (GPO).
  2. Right-click the new GPO and choose Edit.
  3. Expand Computer Configuration > Administrative Templates > Network > Windows Connection Manager.
  4. Double-click the policy Minimize the number of simultaneous connections to the Internet or a Windows Domain.
  5. Select Enabled.
  6. From the Minimize Policy Options drop-down list choose 1 = Minimize simultaneous connections. Optionally you can choose to disable Wi-Fi whenever connected to Ethernet by choosing 3 = Prevent Wi-Fi when on Ethernet.
  7. Click Ok.Always On VPN Trusted Network Detection
  8. Double-click the policy Enable Windows to soft-disconnect a computer from a network.
  9. Select Disabled.
  10. Click Ok.Always On VPN Trusted Network Detection

Additional Information

Understanding and Configuring Windows Connection Manager

Troubleshooting Always On VPN Error 691 and 812 – Part 2

Troubleshooting Always On VPN Error 691 and 812 – Part 2A while back I wrote about troubleshooting and resolving Windows 10 Always On VPN errors 691 and 812. There are numerous issues that can result in these errors, and in that post I pointed out they can be caused by disabling TLS 1.0 on Windows Servers prior to Windows Server 2016. However, administrators may encounter a another scenario in which they receive errors 691 or 812 which is related to Active Directory user account configuration.

SSTP and Error 691

When attempting to establish an Always On VPN connection using the Secure Socket Tunneling Protocol (SSTP), administrators may encounter the following error message.

“The remote connection was denied because the user name and password combination you provided is not recognized, or the selected authentication protocol is not permitted on the remote access server.”

Troubleshooting Always On VPN Error 691 and 812 – Part 2

In addition, an error 691 with event ID 20227 from the RasClient source can be found in the Application event log on the client.

“The user <domain\user> dialed a connection named which has failed. The error code returned on failure is 691.”

Troubleshooting Always On VPN Error 691 and 812 – Part 2

IKEv2 and Error 812

When attempting to establish an Always On VPN connection using Internet Key Exchange version 2 (IKEv2), administrators may encounter the following error message.

“The connection as prevented because of a policy configured on your RAS/VPN server. Specifically, the authentication method used by the server to verify your username and password may not match the authentication method configured in your connection profile. Please contact the Administrator of the RAS server and notify them of this error.”

Troubleshooting Always On VPN Error 691 and 812 – Part 2

In addition, an error 812 with event ID 20227 from the RasClient source can be found in the Application event log on the client.

Troubleshooting Always On VPN Error 691 and 812 – Part 2

NPS Event Log

On the NPS server the administrator will find an entry in the application event log with event ID 6273 from the Microsoft Windows security auditing source and the Network Policy Server task category indicating the network policy server denied access to the user. Looking closely at this event log message shows Reason Code 65 and the following reason.

“The Network Access Permission setting in the dial-in properties of the user account in Active Directory is set to Deny access to the user. To change the Network Access permission setting to either Allow access or Control access through NPS Network Policy, obtain the properties of the user account in Active Directory Users and Computers, click the Dial-in tab, and change Network Access Permission.”

Troubleshooting Always On VPN Error 691 and 812 – Part 2

Resolution

There are two options available to address this issue. The user account in Active Directory can be configured to grant access or allow access to be controlled via NPS network policy, or the NPS network policy can be configured to ignore user account dial-in properties.

User Account

Follow the steps below to change Network Access Permission on an individual user’s Active Directory account.

  1. Open the Active Directory User and Computers (ADUC) management console (dsa.msc) and double-click the user’s account.
  2. Select the Dial-in tab.
  3. In the Network Access Permission section select the option to Allow access or Control access through NPS Network Policy.

Troubleshooting Always On VPN Error 691 and 812 – Part 2

Note: If you do not see the dial-in tab, open the ADUC console on a domain controller. The dial-in tab is not displayed when using the Remote Server Administration Tools (RSAT) for Windows clients.

Network Policy

Follow the steps below to configure NPS network policy to ignore user account dial-in properties.

  1. Open the NPS management console (nps.msc) and double-click the Always On VPN network policy.
  2. In the Access Permission section select Ignore user account dial-in properties.
  3. Click Ok to save the changes.

Troubleshooting Always On VPN Error 691 and 812 – Part 2

Additional Information

Windows 10 Always On VPN Troubleshooting Error 691 and 812

Always On VPN Error Code 858

Always On VPN Error Code 858When configuring Windows 10 Always On VPN using Extensible Authentication Protocol (EAP), the administrator may encounter a scenario in which the client connection fails. The event log will include an event ID 20227 from the RasClient source that includes the following error message.

“The user [domain\username] dialed a connection named [connection name] which has failed. The error code returned on failure is 858.”

Always On VPN Error Code 858

RasClient Error 858

RasClient error code 858 translates to ERROR_EAP_SERVER_CERT_EXPIRED. Intuitively, this indicates that the Server Authentication certificate installed on the Network Policy Server (NPS) has expired. To resolve this issue, renew the certificate on the NPS server.

Additional Information

Windows 10 Always On VPN Network Policy Server (NPS) Load Balancing

Windows 10 Always On VPN and Windows Server 2019 NPS Bug

Windows 10 Always On VPN Error Code 864

Microsoft Intune NDES Connector Error 0x80004003

Microsoft Intune NDES Connector Error 0x80004003To support certificate deployment for non-domain Windows 10 Always On VPN clients, a Windows Server with the Network Device Enrollment Service (NDES) role can be provisioned on-premises. In addition, the Microsoft Intune Connector must be installed and configured on the NDES server to allow Intune-managed clients to request and receive certificates from the on-premises Certification Authority (CA) server.

Connection Status Error

After installing the Microsoft Intune Connector, the administrator may encounter the following error message.

“An error occurred while connecting to the Intune Service. Error code is 0x80004003. The NDES Connector will retry the connection as soon as possible.”

 Microsoft Intune NDES Connector Error 0x80004003

IE Enhanced Security Configuration

This error can occur if Internet Explorer Enhanced Security Configuration (ESC) is enabled. To resolve this issue, disable ESC for administrators and users by opening the Server Manager on the NDES server and performing the following steps.

1. In the navigation pane click Local Server.
2. Click the On link next to IE Enhanced Security Configuration.
3. Click Off in the Administrators section.
4. Click Off in the Users section
5. Click Ok.

Microsoft Intune NDES Connector Error 0x80004003

Once complete, restart the NDES Connector service using the following PowerShell command.

Restart-Service NDESConnectorSvc -PassThru

Additional Configuration

Microsoft Intune NDES Connector Setup Wizard Ended Prematurely

Always On VPN IKEv2 Load Balancing Issue with Kemp LoadMaster

Always On VPN IKEv2 Load Balancing Issue with Kemp LoadMasterA recent update to the Kemp LoadMaster load balancer may cause failed connections for Always On VPN connections using IKEv2. SSTP VPN connections are unaffected.

Load Balancing IKEv2

When using the Kemp LoadMaster load balancer to load balance IKEv2, custom configuration is required to ensure proper operation. Specifically, the virtual service must be configured to use “port following” to ensure both the initial request on UDP port 500 and the subsequent request on UDP port 4500 are sent to the same real server. This requires the virtual service to be configured to operate at layer 7. Detailed configuration guidance for load balancing IKEv2 on the Kemp LoadMaster load balancer can be found here.

Always On VPN IKEv2 Load Balancing Issue with Kemp LoadMaster

Issues with LMOS 7.2.48.0

A recent release of the Load Master Operating System (LMOS) v7.2.48.0 introduced a bug that affects UDP services configured to operate at layer 7, which includes IKEv2. This bug breaks Always On VPN connections using IKEv2, resulting in failed connections. When this occurs, the administrator may encounter an error 809 message for device tunnel or user tunnel.

Always On VPN IKEv2 Load Balancing Issue with Kemp LoadMaster

Update Available

Administrators who use the Kemp LoadMaster load balancer to load balance Always On VPN IKEv2 connections and have updated to LMOS 7.2.48.0 are encouraged to update to LMOS 7.2.48.1 immediately. This latest update includes a fix that resolves broken IKEv2 load balancing for Always On VPN. Once the LoadMaster has been updated to 7.2.48.1, Always On VPN connections using IKEv2 should complete successfully.

Additional Information

Windows 10 Always On VPN IKEv2 Load Balancing and NAT

Windows 10 Always On VPN IKEv2 Load Balancing with Kemp LoadMaster Load Balancer

Windows 10 Always On VPN SSTP Load Balancing with Kemp LoadMaster Load Balancer

Windows 10 Always On VPN Load Balancing with Kemp LoadMaster in Azure

Windows 10 Always On VPN Load Balancing Deployment Guide for Kemp Load Balancers

Microsoft Intune NDES Connector Setup Wizard Ended Prematurely

Microsoft Intune NDES Connector Setup Wizard Ended PrematurelyA Windows Server with the Network Device Enrollment Service (NDES) role can be provisioned on-premises to support certificate deployment for non-domain Windows 10 Always On VPN clients. In addition, the Microsoft Intune Connector must be installed and configured on the NDES server to allow Intune-managed clients to request and receive certificates from the on-premises Certification Authority (CA) server.

Setup Wizard Ended Prematurely

When installing the Microsoft Intune Connector, the administrator may encounter a scenario where the setup wizard fails with the following error message.

“Microsoft Intune Connector Setup Wizard ended prematurely because of an error. Your system has not been modified. To install this program at a later time, run Setup Wizard again. Click the Finish button to exit the Setup Wizard.”

Microsoft Intune NDES Connector Setup Wizard Ended Prematurely

Cryptographic Service Provider

This error can occur if the NDES server certificate template is configured to use the Key Storage Provider cryptography service provider (CSP). When configuring the certificate template for the NDES server, the Legacy Cryptography Service Provider must be used, as shown here.

Microsoft Intune NDES Connector Setup Wizard Ended Prematurely

Additional Information

Deploying Windows 10 Always On VPN with Intune using Custom ProfileXML

Windows 10 Always On VPN Device Tunnel Configuration using Microsoft Intune

Deploying Windows 10 Always On VPN with Microsoft Intune

 

Troubleshooting Always On VPN Error Code 864

When configuring an Always On VPN connection, the administrator may encounter a scenario in which a VPN connection fails using either Internet Key Exchange version 2 (IKEv2) or Secure Socket Tunneling Protocol (SSTP). On the Windows 10 client the error message states the following.

“Can’t connect to [connection name]. The remote access connection completed, but authentication failed because a certificate that validates the server certificate was not found in the Trusted Root Certification Authorities certificate store.”

Troubleshooting Always On VPN Error Code 864

In addition, the Application event log records an error message with Event ID 20227 from the RasClient source. The error message states the following.

“The user [username] dialed a connection name [connection name] which has failed. The error code returned on failure is 864.”

Troubleshooting Always On VPN Error Code 864

NPS Server Certificate

Error code 864 is commonly caused by a missing or invalid server certificate on the Network Policy Server (NPS) performing authentication for VPN clients. The NPS server must have a certificate installed in its local computer certificate store from a trusted certification authority (CA) that includes the following.

Subject Name

The subject name must match the hostname defined in the EAP configuration for VPN clients. This may be the NPS server’s hostname but could also be an alias when NPS load balancing is configured.

Troubleshooting Always On VPN Error Code 864

Enhanced Key Usage

The NPS server certificate must include the Server Authentication Enhanced Key Usage (EKU).

Troubleshooting Always On VPN Error Code 864

NPS Policy Configuration

The NPS server certificate must also be selected in the network policy used for VPN client authentication. To confirm correct certificate configuration, open the properties for the Always On VPN network policy and follow the steps below.

1. Select the Constraints tab.
2. Highlight Authentication Methods.
3. Highlight Microsoft: Protected EAP (PEAP) in the EAP Types field.
4. Click Edit.
5. Select the NPS server certificate from the Certificate issued to drop-down list.

Troubleshooting Always On VPN Error Code 864

Ensure the NPS server certificate is also used for client certificate authentication by performing the following steps.

1. Highlight Smart Card or other certificate.
2. Click Edit.
3. Select the NPS server certificate from the Certificate issued to drop-down list.
4. Click Ok.

Troubleshooting Always On VPN Error Code 864

Additional Information

Windows 10 Always On VPN Network Policy Server (NPS) Load Balancing

Error Importing Windows Server RRAS Configuration

Error Importing Windows Server RRAS Configuration Windows Server and the Routing and Remote Access Service (RRAS) is a popular choice for Windows 10 Always On VPN deployments. It is easy to implement and support, offers flexible scalability, and is cost-effective. In addition, it provides support for a TLS-based VPN protocol which is required for many deployments.

Configuration Backup

When deploying RRAS to support Always On VPN, it’s an excellent idea to export the configuration once all settings have been finalized. Often this is done by opening an elevated command window and running netsh.exe ras dump and piping the output to a text file, as shown here.

netsh.exe ras dump > rasconfig.txt

Import Error

Importing a saved configuration is accomplished by opening an elevated command window and running netsh.exe exec [filename], as shown here.

netsh.exe exec rasconfig.txt

Oddly, this doesn’t work by default. The import will fail and return the following error message.

“The following command was not found: ■.”

Error Importing Windows Server RRAS Configuration

Root Cause

Importing the RRAS configuration fails because the default configuration output is saved in Unicode format. Inexplicably this encoding is not recognized by netsh.exe when importing the configuration.

Workaround

Follow the steps below to save the configuration file in a format that can be imported using netsh.exe.

1. Open the exported configuration file using notepad.exe.
2. From the Menu bar choose File > Save As.
3. From the Encoding drop-down list choose ANSI.
4. Click Save.

Error Importing Windows Server RRAS Configuration

Once complete, import the file using netsh.exe exec [filename]. Restart the RemoteAccess service to apply the changes.

PowerShell

Administrators can use PowerShell to export the RRAS configuration and ensure the correct encoding format is used by default. To do this, open an elevated PowerShell window and run the following command.

Invoke-Command -ScriptBlock {netsh ras dump} | Out-File [filename] -Encoding ASCII

You can also find PowerShell script to import and export RRAS configuration on my Github.

Export-VpnServerConfiguration.ps1

Import-VpnServerConfiguration.ps1

Additional Information

Windows 10 Always On VPN and Windows Server Routing and Remote Access Service (RRAS)

Windows 10 Always On VPN Protocol Recommendations for Windows Server Routing and Remote Access Service (RRAS)

Always On VPN Clients Prompted for Authentication when Accessing Internal Resources

Always On VPN Clients Prompted for Authentication when Accessing Internal ResourcesWhen deploying Windows 10 Always On VPN using Protected Extensible Authentication Protocol (PEAP) with client authentication certificates, the administrator may encounter a scenario in which the user can establish a VPN connection without issue, but when accessing internal resources they are prompted for credentials and receive the following error message.

“The system cannot contact a domain controller to service the authentication request. Please try again later.”

Always On VPN Clients Prompted for Authentication when Accessing Internal Resources

Resolution

This can occur if one or more domain controllers in the enterprise have expired or missing domain controller authentication certificates. To ensure seamless single sign-on to internal resources, ensure that all domain controllers have a certificate issued by the internal certification authority (CA) that includes the Server Authentication (1.3.6.1.5.5.7.3.1), Client Authentication (1.3.6.1.5.5.7.3.2), KDC Authentication (1.3.6.1.5.2.3.5), and Smart Card Logon (1.3.6.1.4.1.311.20.2.2) Enhanced Key Usage (EKU). Administrators can duplicate the Kerberos Authentication template for this purpose.

Always On VPN Clients Prompted for Authentication when Accessing Internal Resources

Additional Information

Windows 10 Always On VPN Certificate Requirements for IKEv2

Windows 10 Always On VPN Hands-On Training

 

Renew DirectAccess Self-Signed Certificates

Renew DirectAccess Self-Signed CertificatesImportant! Updated April 29, 2020 to resolve an issue where the DirectAccess RADIUS encryption certificate was not published to the DirectAccess Server Settings GPO in Active Directory.

When DirectAccess is deployed using the Getting Started Wizard (GSW), sometimes referred to as the “simplified deployment” method, self-signed certificates are created during the installation and used for the IP-HTTPS IPv6 transition technology, the Network Location Server (NLS), and for RADIUS secret encryption. Administrators may also selectively choose to use self-signed certificates for IP-HTTPS, or when collocating the NLS on the DirectAccess server. The RADIUS encryption certificate is always self-signed.

Renew DirectAccess Self-Signed Certificates

Certificate Expiration

These self-signed certificates expire 5 years after they are created, which means many DirectAccess administrators who have used this deployment option will need to renew these certificates at some point in the future. Unfortunately, there’s no published guidance from Microsoft on how to accomplish this. However, the process is simple enough using PowerShell and the New-SelfSignedCertificate cmdlet.

PowerShell Script on GitHub

The PowerShell script to renew DirectAccess self-signed certificates has been published on GitHub. You can download Renew-DaSelfSignedCertificates.ps1 here.

Important Considerations

When the IP-HTTPS certificate is renewed using this script, DirectAccess clients outside will be immediately disconnected and will be unable to reconnect until they update group policy. This will require connecting to the internal network locally or remotely using another VPN solution. The NLS and RADIUS encryption certificates can be updated without impacting remote users.

In addition, internal clients that are not online when this change is made will be unable to access internal resources by name until they update group policy. If this happens, delete the Name Resolution Policy Table (NRPT) on the client using the following PowerShell command and reboot to restore connectivity.

Get-Item -Path “HKLM:\SOFTWARE\Policies\Microsoft\Windows NT\DNSClient\DnsPolicyConfig” | Remove-Item -Confirm:$false

Additional Information

PowerShell Recommended Reading for DirectAccess Administrators

Top 5 DirectAccess Troubleshooting PowerShell Commands

 

 

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