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

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

 

Always On VPN Device Tunnel and Certificate Revocation

Always On VPN Device Tunnel and Certificate RevocationRecently I wrote about denying access to Windows 10 Always On VPN users or computers. In that post I provided specific guidance for denying access to computers configured with the device tunnel. To summarize, the process involved exporting the device certificate from the issuing Certification Authority (CA) server and placing it in the Untrusted Certificates certificate store on each VPN server. In theory, simply revoking the device certificate should be all that’s required to prevent device tunnel connections.

Revocation Check Failure

As it turns out, a bug in Windows Server Routing and Remote Access prevents this from working as expected. Windows Server 2012 R2, 2016, and 2019 all fail to check the Certificate Revocation List (CRL) for IKEv2 VPN connections using machine certificate authentication (for example an Always On VPN device tunnel).

Updates for Windows Server

Microsoft has released fixes to support device tunnel certificate revocation for the following operating systems.

Windows Server 2019 – KB4505658 (build 17763.652)

Windows Server 2016 – KB4503294 (build 14393.3053)

Windows Server 2012/R2 – Will not be updated.

Enable Revocation Check

Additional configuration is required to enable support for CRL checking. Microsoft published guidance for configuring CRL revocation checks for IKEv2 VPN connections using machine certificate authentication here. Specifically, administrators must enable the RootCertificateNameToAccept parameter and set a registry key to enable this functionality.

Open an elevated PowerShell window and run the following commands to enable CRL checking for IKEv2 VPN connections using machine certificate authentication.

$Thumbprint = ‘Root CA Certificate Thumbprint’
$RootCACert = (Get-ChildItem -Path cert:\LocalMachine\root | Where-Object {$_.Thumbprint -eq $Thumbprint})
Set-VpnAuthProtocol -RootCertificateNameToAccept $RootCACert -PassThru

New-ItemProperty -Path ‘HKLM:\SYSTEM\CurrentControlSet\Services\RemoteAccess\Parameters\Ikev2\’ -Name CertAuthFlags -PropertyTYpe DWORD -Value ‘4’ -Force

Restart-Service RemoteAccess -PassThru

Always On VPN Device Tunnel and Certificate Revocation

A PowerShell script to update the RootCertificateNameToAccept parameter on multiple VPN servers can be found here.

Revoking Certificates

To prevent a Windows 10 Always On VPN device tunnel connection, the administrator must first revoke the certificate on the issuing CA. Next, open an elevated command window an enter the following commands. Repeat these steps on each VPN server in the enterprise.

certutil -urlcache * delete
certutil -setreg chain\ChainCacheResyncFiletime @now

Additional Information

Denying Access to Windows 10 Always On VPN Users or Computers

Blocking VPN Clients that use Revoked Certificates

PowerShell Script to Configure RootCertificateNameToAccept on GitHub

 

 

Always On VPN SSTP Connects then Disconnects

Always On VPN SSTP Connects then DisconnectsWhen Always On VPN clients are configured to use the Secure Socket Tunneling Protocol (SSTP) with Windows Server Routing and Remote Access Service (RRAS), administrators may encounter a scenario in which a client can establish a VPN connection using SSTP successfully, but is then disconnected immediately. The system event log contains an entry with Event ID 6 from the RasSstp source that includes the following error message.

“The SSTP-based VPN connection to the remote access server was terminated because of a security check failure. Security settings on the remote access server do not match settings on this computer. Contact the system administrator of the remote access server and relay the following information.”

Always On VPN Connect and Disconnect with SSTP

Common Causes

The two most common causes of this issue are when SSTP is configured for SSL offload, and when a VPN client is on a network where SSL inspection is taking place.

SSTP Offload

The most common cause of this issue is when SSL offload is configured for SSTP on an external load balancer or application delivery controller (ADC). To prevent interception from a Man-in-the-Middle attack, the VPN client sends the certificate hash of the SSL certificate used when the VPN connection was established. If this information does not match what is configured on the RRAS server, the connection is assumed to be compromised and the connection is immediately dropped.

SSL Inspection

Another scenario where this issue may occur is when a VPN client is behind a network device configured to perform SSL deep-packet inspection (DPI). SSTP VPN clients will be unable to connect to the VPN server in this scenario.

Resolution

When offloading SSL to another device, the RRAS server must be configured to know which SSL certificate is being presented to remote clients. This information is stored in the following registry key.

HKLM:\SYSTEM\CurrentControlSet\Services\SstpSvc\Parameters\SHA256CertificateHash

However, this registry entry requires a binary value, which makes it a challenge to configure manually. To resolve this problem, it is recommended that the same SSL certificate installed on the load balancer/ADC also be installed on the VPN server (even though SSL will be offloaded). To do this, first import the SSL certificate and private key in to the Local Computer certificate store, then open the RRAS management console and perform the following steps.

  1. Right-click the VPN server and choose Properties.
  2. Select the Security tab.
  3. Uncheck Use HTTP in the SSL Certificate Binding section.
  4. Select the appropriate SSL certificate from the Certificate drop-down list (click View to verify).
  5. Click Apply.

This will add the correct SSL certificate information to the registry. Next, re-enable HTTP for SSL offload by performing the following steps.

  1. Check Use HTTP in the SSL Certificate Binding section.
  2. Click Apply.

PowerShell Configuration

If the SSL certificate cannot be installed on the VPN server, or to automate this configuration across multiple servers remotely, download and run the Enable-SstpOffload PowerShell script from my GitHub repository here and run the following command.

Enable-SSTPOffload -CertificateHash [SHA256 Certificate Hash of Public SSL Certificate] -Restart

For example…

Enable-SSTPOffload -CertificateHash “C3AB8FF13720E8AD9047DD39466B3C8974E592C2FA383D4A3960714CAEF0C4F2” -Restart

Additional Information

Windows 10 Always On VPN Load Balancing and SSL Offload

Windows 10 Always On VPN SSTP Load Balancing with F5 BIG-IP

Windows 10 Always On VPN SSL Certificate Requirements for SSTP

Windows 10 Always On VPN Protocol Recommendations for Windows Server RRAS

 

Always On VPN and Network Policy Server (NPS) Load Balancing

Always On VPN and Network Policy Server (NPS) Load BalancingLoad balancing Windows Server Network Policy Servers (NPS) is straightforward in most deployment scenarios. Most VPN servers, including Windows Server Routing and Remote Access Service (RRAS) servers allow the administrator to configure multiple NPS servers for redundancy and scalability. In addition, most solutions support weighted distribution, allowing administrators to distribute requests evenly between multiple NPS servers (round robin load balancing) or to distribute them in order of priority (active/passive failover).

The Case for NPS Load Balancing

Placing NPS servers behind a dedicated network load balancing appliance is not typically required. However, there are some deployment scenarios where doing so can provide important advantages.

Deployment Flexibility

Having NPS servers fronted by a network load balancer allows the administrator to configure a single, virtual IP address and hostname for the NPS service. This provides deployment flexibility by allowing administrators to add or remove NPS servers without having to reconfigure VPN servers, network firewalls, or VPN clients. This can be beneficial when deploying Windows updates, migrating NPS servers to different subnets, adding more NPS servers to increase capacity, or performing rolling upgrades of NPS servers.

Traffic Shaping

Dedicated network load balancers allow for more granular control and of NPS traffic. For example, NPS routing decisions can be based on real server availability, ensuring that authentication requests are never sent to an NPS server that is offline or unavailable for any reason. In addition, NPS traffic can be distributed based on server load, ensuring the most efficient use of NPS resources. Finally, most load balancers also support fixed or weighted distribution, enabling active/passive failover scenarios if required.

Traffic Visibility

Using a network load balancer for NPS also provides better visibility for NPS authentication traffic. Most load balancers feature robust graphical displays of network utilization for the virtual server/service as well as backend servers. This information can be used to ensure enough capacity is provided and to monitor and plan for additional resources when network traffic increases.

Configuration

Before placing NPS servers behind a network load balancer, the NPS server certificate must be specially prepared to support this unique deployment scenario. Specifically, the NPS server certificate must be configured with the Subject name of the cluster, and the Subject Alternative Name field must include both the cluster name and the individual server’s hostname.

Always On VPN and Network Policy Server (NPS) Load Balancing

Always On VPN and Network Policy Server (NPS) Load Balancing

Create Certificate Template

Perform the following steps to create a certificate template in AD CS to support NPS load balancing.

  1. Open the Certificate Templates management console (certtmpl.msc) on the certification authority (CA) server or a management workstation with remote administration tool installed.
  2. Right-click the RAS and IAS Servers default certificate template and choose Duplicate.
  3. Select the Compatibility tab.
    1. Select Windows Server 2008 or a later version from the Certification Authority drop-down list.
    2. Select Windows Vista/Server 2008 or a later version from the Certificate recipient drop-down list.
  4. Select the General tab.
    1. Enter a descriptive name in the Template display name field.
    2. Choose an appropriate Validity period and Renewal period.
    3. Do NOT select the option to Publish certificate in Active Directory.
  5. Select the Cryptography tab.
    1. Chose Key Storage Provider from the Provider Category drop-down list.
    2. Enter 2048 in the Minimum key size field.
    3. Select SHA256 from the Request hash drop-down list.
  6. Select the Subject Name tab.
    1. Select the option to Supply in the request.
  7. Select the Security tab.
    1. Highlight RAS and IAS Servers and click Remove.
    2. Click Add.
    3. Enter the security group name containing all NPS servers.
    4. Check the Read and Enroll boxes in the Allow column in the Permissions for [group name] field.
  8. Click Ok.

Perform the steps below to publish the new certificate template in AD CS.

  1. Open the Certification Authority management console (certsrv.msc) on the certification authority (CA) server or a management workstation with remote administration tool installed.
  2. Expand Certification Authority (hostname).
  3. Right-click Certificate Templates and choose New and Certificate Template to Issue.
  4. Select the certificate template created previously.
  5. Click Ok.

Request Certificate on NPS Server

Perform the following steps to request a certificate for the NPS server.

  1. Open the Certificates management console (certlm.msc) on the NPS server.
  2. Expand the Personal folder.
  3. Right-click Certificates and choose All Tasks and Request New Certificate.
  4. Click Next.
  5. Click Next.
  6. Select the NPS server certificate template and click More information is required to enroll for this certificate link.
  7. Select the Subject tab.
    1.  Select Common name from the Type drop-down list in the Subject name section.
    2. Enter the cluster fully-qualified hostname (FQDN) in the Value field.
    3. Click Add.
    4. Select DNS from the Type drop-down list in the Alternative name section.
    5. Enter the cluster FQDN in the Value field.
    6. Click Add.
    7. Enter the NPS server’s FQDN in the Value field.
    8. Click Add.
      Always On VPN and Network Policy Server (NPS) Load Balancing
  8. Select the General tab.
    1. Enter a descriptive name in the Friendly name field.
  9. Click Ok.
  10. Click Enroll.

Load Balancer Configuration

Configure the load balancer to load balance UDP ports 1812 (authentication) and 1813 (accounting). Optionally, to ensure that authentication and accounting requests go to the same NPS server, enable source IP persistence according to the vendor’s guidance. For the KEMP LoadMaster load balancer, the feature is called “port following”. On the F5 BIG-IP it is called a “persistence profile”, and on the Citrix NetScaler it is called a “persistency group”.

Additional Information

Always On VPN IKEv2 Load Balancing with KEMP LoadMaster

Always On VPN Hands-On Training Classes in U.S. and Europe

Always On VPN IKEv2 Security Configuration

Always On VPN IKEv2 Security ConfigurationWhen deploying Windows 10 Always On VPN, many administrators choose the Internet Key Exchange version 2 (IKEv2) protocol to provide the highest level of security and protection for remote connections. However, many do not realize the default security parameters for IKEv2 negotiated between a Windows Server running the Routing and Remote Access Service (RRAS) and a Windows 10 VPN client are far less than ideal from a security perspective. Additional configuration on both the server and the client will be required to ensure adequate security and protection for IKEv2 VPN connections.

Windows 10 and RRAS IKEv2 Defaults

In their default configuration, a Windows 10 client connecting to a Windows Server running RRAS will negotiate an IKEv2 VPN connection using the following IPsec security parameters.

  • Encryption: 3DES
  • Authentication/Integrity: SHA-1
  • Key Size: DH Group 2 (1024 bit)

This information can be obtained by opening an elevated PowerShell command window and running the following command.

Get-NetIPsecMainModeSA | Select-Object -First 1

Always On VPN IKEv2 Security Configuration

This can also be confirmed by viewing a network trace as shown here.

Always On VPN IKEv2 Security Configuration

These IPsec security parameters might have been acceptable in the 90’s, but they certainly are not today. 🙂

Improving IKEv2 Security

To provide a baseline level of protection to meet today’s requirements for security and privacy for IKEv2 VPN connections, the following are the minimum recommended IPsec security parameters.

  • Encryption: AES128
  • Authentication/Integrity: SHA-256
  • Key Size: DH Group 14 (2048 bit)

RRAS Custom IPsec Policy

To implement these recommended security baselines for IKEv2 on a Windows Server running RRAS it will be necessary to define a custom IPsec security policy. To do this, open an elevated PowerShell command window and run the following commands on each RRAS server.

Set-VpnServerConfiguration -CustomPolicy -AuthenticationTransformConstants SHA256128 -CipherTransformConstants AES128 -DHGroup Group14 -EncryptionMethod AES128 -IntegrityCheckMethod SHA256 -PFSgroup PFS2048 -SADataSizeForRenegotiationKilobytes 102400

Restart the Remote Access Management service for the changes to take effect.

Restart-Service RemoteAccess -PassThru

Always On VPN IKEv2 Security Configuration

Note: A PowerShell script to implement the custom IPsec security policy settings shown above can be downloaded here.

Windows 10 Client Settings

The IPsec policy must match on both the server and the client for an IKEv2 VPN connection to be successful. Unfortunately, none of the IKEv2 IPsec security association parameters proposed by default on Windows 10 clients use 2048-bit keys (DH Group 14), so it will be necessary to define a custom IPsec security policy on the client to match the settings configured on the server.

To configure a matching IPsec security policy on an individual Windows 10 VPN client, open an elevated PowerShell command window and run the following command.

$connection = “[connection name]”
Set-VpnConnectionIPsecConfiguration -ConnectionName $connection -AuthenticationTransformConstants SHA256128 -CipherTransformConstants AES128 -DHGroup Group14 -EncryptionMethod AES128 -IntegrityCheckMethod SHA256 -PFSgroup PFS2048 -Force

Always On VPN IKEv2 Security Configuration

Restore Defaults

In the process of testing it may be necessary to restore the default IKEv2 configuration on both the client and the server. This can be accomplished by running the following PowerShell commands.

Server – Set-VpnServerConfiguration -RevertToDefault

Client – Set-VpnConnectionIPsecConfiguration -ConnectionName [connection_name] -RevertToDefault -Force

Always On VPN XML Settings

To implement a custom IPsec policy using the minimum recommended security settings for an Always On VPN connection using IKEv2, add the following settings to your ProfileXML.

<VPNProfile>
 <NativeProfile>
  <CryptographySuite>
   <AuthenticationTransformConstants>SHA256128</AuthenticationTransformConstants>
   <CipherTransformConstants>AES128</CipherTransformConstants>
   <EncryptionMethod>AES128</EncryptionMethod>
   <IntegrityCheckMethod>SHA256</IntegrityCheckMethod>
   <DHGroup>Group14</DHGroup>
   <PfsGroup>PFS2048</PfsGroup>
  </CryptographySuite>
 </NativeProfile>
</VPNProfile>

Why Not AES 256?

In the examples above you’ll notice that I’ve chosen to use AES128 and not AES256. This is by design, as AES256 does not provide any practical additional security in most use cases. Details here.

Enhanced Security and Performance

To further improve security and performance for IKEv2, consider implementing Elliptic Curve Cryptography (EC) certificates and using Galois Counter Mode (GCM) cipher suites such as GCMAES128 for authentication and encryption.

Additional Information

Always On VPN Certificate Requirements for IKEv2

Always On VPN IKEv2 Connection Failure Error Code 800

Always On VPN IKEv2 Load Balancing with the KEMP LoadMaster Load Balancer

 

Troubleshooting Always On VPN Error Code 0x80092013

Troubleshooting Always On VPN Error Code 0x80092013Windows Server Routing and Remote Access Service (RRAS) is commonly used for Windows 10 Always On VPN deployments because it is easy to configure and manage and it includes Microsoft’s proprietary Secure Socket Tunneling Protocol (SSTP). SSTP is a Transport Layer Security (TLS) VPN protocol that is firewall-friendly and ubiquitously available. However, a common configuration mistake can lead to failed connections.

Error 0x80092013

A Windows 10 Always On VPN client may fail to establish a VPN connection to an RRAS VPN server when using SSTP. The VPN client will return the following error message.

“Can’t connect to Always On VPN. The revocation function was unable to check revocation because the revocation server was offline.”

Troubleshooting Always On VPN Error Code 0x80092013

The event log will also include RasClient event ID 20227 with the following error.

“The user [domain\user] dialed a connection named [connection name] which has failed. The error code returned on failure is -2146885613.”

Troubleshooting Always On VPN Error Code 0x80092013

The Win32 error code –2146885613 converts to hexadecimal 0x80092013, which translates to CRYPT_E_REVOCATION_OFFLINE, indicating that the client was unable to successfully perform a check of the VPN server’s SSL certificate.

Revocation Checking

When the VPN client attempts to establish an SSTP connection to the Windows RRAS VPN, it will check the Certification Revocation List (CRL) using the information provided in the SSL certificate. If the CRL is unreachable for any reason, the client will not complete the connection

Common Cause of Error 0x80092013

Certificate revocation failures for Windows 10 Always On VPN SSTP connections commonly occur when the RRAS VPN server is configured with an SSL certificate issued by an internal certification authority (CA) and the CRL is not publicly available.

Resolving Error 0x80092013

Making the internal CA’s CRL available publicly will of course resolve this error. However, best practice recommendations for the SSTP SSL certificate call for the use of a certificate issued by a public CA. For detailed information about SSL certificate requirements and recommendations, please see Always On VPN SSL Certificate Requirements for SSTP.

Additional Information

Always On VPN SSL Certificate Requirements for SSTP

Always On VPN ECDSA SSL Certificate Request for SSTP

Always On VPN Protocol Recommendations for Windows RRAS

Always On VPN Certificate Requirements for IKEv2

Always On VPN Certificate Requirements for IKEv2Internet Key Exchange version 2 (IKEv2) is one of the VPN protocols supported for Windows 10 Always On VPN deployments. When the VPN server is Windows Server 2016 with the Routing and Remote Access Service (RRAS) role configured, a computer certificate must first be installed on the server to support IKEv2. There are some unique requirements for this certificate, specifically regarding the subject name and Enhanced Key Usage (EKU) configuration. In addition, some deployment scenarios may require a certificate to be provisioned to the client to support IKEv2 VPN connections.

Server Certificate

The IKEv2 certificate on the VPN server must be issued by the organization’s internal private certification authority (CA). It must be installed in the Local Computer/Personal certificate store on the VPN server. The subject name on the certificate must match the public hostname used by VPN clients to connect to the server, not the server’s hostname. For example, if the VPN server’s hostname is VPN1 and the public FQDN is vpn.example.net, the subject field of the certificate must include vpn.example.net, as shown here.

Always On VPN Certificate Requirements for IKEv2

In addition, the certificate must include the Server Authentication EKU (1.3.6.1.5.5.7.3.1). Optionally, but recommended, the certificate should also include the IP security IKE intermediate EKU (1.3.6.1.5.5.8.2.2).

Always On VPN Certificate Requirements for IKEv2

Client Certificate

Client certificate requirements vary depending on the type of VPN tunnel and authentication method being used.

User Tunnel

No certificates are required on the client to support IKEv2 when using MSCHAPv2, EAP-MSCHAPv2, or Protected EAP (PEAP) with MSCHAPv2. However, if the option to verify the server’s identity by validating the certificate is selected when using PEAP, the client must have the certificates for the root CA and any subordinate CAs installed in its Trusted Root Certification and Intermediate Certificate Authorities certificate stores, respectively.

User Tunnel with Certificate Authentication

Using certificate authentication for the user tunnel is the recommended best practice for Always On VPN deployments. A client certificate must be installed in the Current User/Personal store to support PEAP authentication with smart card or certificate authentication. The certificate must include the Client Authentication EKU (1.3.6.1.5.5.7.3.2).

Always On VPN Certificate Requirements for IKEv2

Device Tunnel

A computer certificate must be installed in the Local Computer/Personal certificate store to support IKEv2 machine certificate authentication and the Always On VPN device tunnel. The certificate must include the Client Authentication EKU (1.3.6.1.5.5.7.3.2).

Always On VPN Certificate Requirements for IKEv2

More information about configuring the Always On VPN device tunnel can be found here.

Additional Information

Always On VPN with Trusted Platform Module (TPM) Certificates

Always On VPN Protocol Recommendations for Windows Server 2016 RRAS

Always On VPN and Windows Server RRAS

Always On VPN Training

DirectAccess IP-HTTPS and Symantec SSL Certificates

DirectAccess IP-HTTPS and Symantec SSL CertificatesAn SSL certificate is required to support the IP-HTTPS IPv6 transition technology when configuring DirectAccess. Implementation best practices dictate using a public SSL certificate signed by a trusted third-party vendor such as Entrust, Verisign, DigiCert, and others. SSL certificates issued by a private PKI are acceptable if the client trusts the issuing CA. Self-signed certificates are supported in some deployment scenarios, but their use is generally discouraged. For more detailed information regarding SSL certificate considerations for DirectAccess IP-HTTPS click here.

Symantec Issued Certificates

Symantec is a popular commercial SSL certificate provider that has been commonly used for many years. However, due to integrity issues associated with their PKI management practices, Google and Mozilla announced they will soon be deprecating these certificates. This means users who browse to an HTTPS web site protected with a Symantec SSL certificate will receive a warning in their browser indicating the certificate is not trusted.

DirectAccess IP-HTTPS

It is important to note that there is no impact at all for DirectAccess when the server is configured to use an SSL certificate issued by Symantec. There is nothing you need to do to address this issue in this scenario. However, if a wildcard certificate is installed on the DirectAccess server and it is also used on other public-facing web servers in the organization, it is likely that the certificate will replaced, perhaps by another certificate provider. In this case, DirectAccess IP-HTTPS must be configured to use the new or updated SSL certificate.

Updating IP-HTTPS SSL Certificate

To update the DirectAccess IP-HTTPS SSL certificate, import the SSL certificate along with the private key in to the local computer certificate store on each DirectAccess server. Next identify the thumbprint of the new SSL certificate. Finally, open an elevated PowerShell command window and enter the following command.

$thumbprint = “ssl_cert_thumbprint”
$cert = Get-ChildItem -Path cert:\localmachine\my | where {$_.thumbprint -eq $thumbprint}
Set-RemoteAccess -SslCertificate $cert -PassThru

Be sure to replace “ssl_cert_thumbprint” with the actual thumbprint of your SSL certificate. 😉 In addition, for load-balanced and/or multisite deployments, run these PowerShell commands on each server in the enterprise.

Additional Information

SSL Certificate Considerations for DirectAccess IP-HTTPS

DirectAccess IP-HTTPS Null Cipher Suites Not Available 

DirectAccess IP-HTTPS Performance Issues

DirectAccess and Always On VPN with Trusted Platform Module (TPM) Certificates

DirectAccess and Always On VPN with Trusted Platform Module (TPM) CertificatesTo enhance security when provisioning certificates for DirectAccess (computer) or Windows 10 Always On VPN (user) it is recommended that private keys be stored on a Trusted Platform Module (TPM) on the client device. A TPM is a dedicated security processor included in nearly all modern computers. It provides essential hardware protection to ensure the highest levels of integrity for digital certificates and is used to generate, store, and restrict the use of cryptographic keys. It also includes advanced security and protection features such as key isolation, non-exportability, and anti-hammering to prevent brute-force attacks.

To ensure that private keys are created and stored on a TPM, the certificate template must be configured to use the Microsoft Platform Crypto Provider. Follow the steps below to configure a certificate template required to use a TPM.

  1. Open the Certificate Templates management console (certtmpl.msc) and duplicate an existing certificate template. For example, if creating a certificate for DirectAccess, duplicate the Workstation Authentication certificate template. For Always On VPN, duplicate the User certificate template.
  2. On the Compatibility tab, ensure the Certification Authority and Certificate recipient compatibility settings are set to a minimum of Windows Server 2008 and Windows Vista/Server 2008, respectively.DirectAccess and Always On VPN with Trusted Platform Module (TPM) Certificates
  3. Select the Cryptography tab.
  4. Choose Key Storage Provider from the Provider Category drop down list.
  5. Choose the option Requests must use one of the following providers and select Microsoft Platform Crypto Provider.DirectAccess and Always On VPN with Trusted Platform Module (TPM) Certificates

Note: If Microsoft Platform Crypto Provider does not appear in the list above, got to the Request Handling tab and uncheck the option Allow private key to be exported.

Complete the remaining certificate configuration tasks (template display name, subject name, security settings, etc.) and publish the certificate template. Client machines configured to use this template will now have a certificate with private key fully protected by the TPM.

Additional Resources

Trusted Platform Module (TPM) Fundamentals

DirectAccess and Always On VPN Certificate Auto Enrollment

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