Always On VPN Trusted Network Detection and Native Azure AD Join

Administrators deploying Microsoft Always On VPN are quickly learning that the native Azure Active Directory join (AADJ) model has significant advantages over the more traditional Hybrid Azure AD join (HAADJ) scenario. Native AADJ is much simpler to deploy and manage than HAADJ while still allowing full single sign-on (SSO) to on-premises resources for remote users. Intune even allows for the import of custom ADMX and ADML administrative templates, further reducing the dependency on on-premises Active Directory for device management.

Remote Management

Although devices aren’t joined to the domain, administrators may still wish to access those clients connected to their network for device discovery or to perform administrative tasks. However, when native AADJ clients connect via Always On VPN, the Public Windows firewall profile is assigned to the VPN tunnel adapter. The Public profile is, of course, more restrictive and blocks most management protocols by default.

Firewall Rules

While adding firewall rules to the Public profile to allow management protocols is possible, this isn’t recommended for security reasons. The Public profile is typically loaded when the device is on an untrusted network. Exposing management protocols on an insecure network is asking for trouble.

Domain Profile

Domain-joined or Hybrid AADJ endpoints will use the Domain Windows firewall profile. This profile is more permissive, allowing many standard management protocols by default. Also, administrators can add rules to allow additional access as required without increasing the risk for devices on untrusted networks.

Trusted Network Detection

So, the trick is to get a native AADJ endpoint to load the Domain profile for the VPN tunnel adapter when connected via Always On VPN. Trusted Network Detection is accomplished by using settings configured on the endpoint using the NetworkListManager Configuration Service Provider (CSP).

Intune and XML

There are two settings administrators can enable AADJ devices to detect a trusted network and load the Domain Windows firewall profile. Unfortunately, these settings can only be applied using Intune and the Custom XML template. Administrators will use the following OMA-URI settings.


The AllowedTlsAuthenticationEndpoints policy setting defines the URL the device uses to validate a trusted network. The target must be an on-premises web server with a valid TLS certificate using HTTPS. The target must be a highly available internal resource inaccessible from the Internet. DirectAccess administrators will be quite familiar with this concept; it’s the Network Location Server (NLS)!

Use the following OMA-URI to configure the TLS authentication endpoint.

URI: ./Device/Vendor/MSFT/Policy/Config/

String: <![CDATA[]]>


The ConfiguredTlsAuthenticationNetworkName policy setting is optional. Administrators can use this setting to provide a friendly name for the authenticated trusted network. The FQDN of the target resource (NLS) is used by default. However, using this setting overrides the default with something more meaningful.

Use the following OMA-URI to configure the TLS authentication network name.

URI: ./Device/Vendor/MSFT/Policy/Config/

String: <Friendly network name>


Once configured, you’ll find the Always On VPN tunnel adapter uses the Domain Windows firewall profile and an optional friendly network name.

Additional Information

Deploying Always On VPN with Intune using Custom XML and CSP

Always On VPN CSP Updates

Always On VPN and VpnStrategy with CSP

Troubleshooting DirectAccess IP-HTTPS Error 0x2af9

When troubleshooting DirectAccess client connectivity issues, you may encounter a scenario where clients are unable to connect using the IP-HTTPS IPv6 transition technology. Running ipconfig shows that the tunnel adapter IPHTTPSInterface media state is Media disconnected.

DirectAccess IP-HTTPS Error 0x2af9

Running the Get-NetIpHttpsState PowerShell command shows that the LastErrorCode is 0x2af9 (WSAHOST_NOT_FOUND) and the InterfaceStatus is Failed to connect to the IPHTTPS server; waiting to reconnect.

DirectAccess IP-HTTPS Error 0x2af9

The 0x2af9 error differs slightly from the more common 0x274c IP-HTTPS connection time out error (WSAETIMEDOUT). In this scenario the DirectAccess client can successfully resolve the DirectAccess public hostname to an IPv4 address, and if ICMP echo requests are allowed on the DirectAccess server’s public IPv4 address it will respond to ping.

DirectAccess IP-HTTPS Error 0x2af9

The DirectAccess client is also able to establish a TCP connection to the DirectAccess server using the Test-NetConnection PowerShell command.

DirectAccess IP-HTTPS Error 0x2af9

So, why is the IP-HTTPS interface unable to establish a transition tunnel connection when the DirectAccess server’s public hostname resolves correctly via DNS and the client can establish a TCP connection on port 443? Commonly this is caused by proxy server settings configured in the web browser on the DirectAccess client computer. Disabling the proxy server in the client’s web browser should restore DirectAccess client connectivity over IP-HTTPS.

DirectAccess IP-HTTPS Error 0x2af9

If clearing the proxy server settings in the client machine’s web browser still does not restore IP-HTTPS connectivity, it may be that a proxy server is also configured for winhttp. You can confirm this by opening an elevated PowerShell command window and running the netsh winhttp show proxy command.

DirectAccess IP-HTTPS Error 0x2af9

To clear the winhttp proxy server settings run the netsh winhttp reset proxy command.

DirectAccess IP-HTTPS Error 0x2af9

Additional Resources

DirectAccess Expired IP-HTTPS Certificate and Error 0x800b0101

DirectAccess IP-HTTPS Preauthentication

DirectAccess SSL Offload and IP-HTTPS Preauthentication with Citrix NetScaler

DirectAccess SSL Offload using F5 BIG-IP

DirectAccess IP-HTTPS Preauthentication with F5 BIG-IP

DirectAccess and Multi-SAN SSL Certificates for IP-HTTPS

SSL Certificate Considerations for DirectAccess IP-HTTPS

Implementing DirectAccess with Windows Server 2016 Book