Always On VPN Error -2146762495

DirectAccess Troubleshooting and the Windows 10 Network Connectivity Assistant

Always On VPN Administrators may encounter a scenario where Always On VPN connections suddenly stop working for all clients using the Secure Socket Tunneling Protocol (SSTP) VPN protocol. IKEv2 VPN connections continue to work, however.

Event Log

Reviewing the event log on a client machine reveals an error event ID 20227 from the RasClient source. The error message states the following.

“The user [username] dialed a connection named [connection name] which has failed. The error code returned on failure is -2146762495.”

Error -2146762495?

Always On VPN administrators will be familiar with error codes such as 809, 691 and 812, 853, 858, and even 13801, 13806, and 13868. However, this error code seems to be formatted much differently. As it turns out, this message is in decimal format. Thankfully it’s pretty easy to convert it to something more meaningful, like hexadecimal. To do this, open the Windows calculator (calc.exe) and switch to programmer mode. Highlight DEC and enter -2146762495. The hexadecimal value will be displayed in the HEX field, as shown here.

Error 0x800B0101

After converting the error message from decimal to hex, use the Microsoft Error Lookup tool (err.exe) to translate the hex value of this error. As shown here, 0x800B0101 translates to CERT_E_EXPIRED.

Expired TLS Certificate

Once again, an expired certificate is to blame! In this case, the TLS certificate installed on the VPN server has expired and is no longer valid.

Resolution

The problem is simple enough to resolve, of course. Obtain a new TLS certificate from your certification authority (CA) of choice and update your VPN server configuration. You can find detailed guidance for updating the RRAS VPN server’s TLS certificate here. You will also find a video demonstration of the RRAS SSL/TLS certificate renewal process here.

Additional Information

Installing or Renewing an SSL/TLS Certificate on Windows Server RRAS for Always On VPN and SSTP

VIDEO: Installing or Renewing an SSL/TLS certificate on Windows Server RRAS for Always On VPN and SSTP

Microsoft Windows Always On VPN SSTP Security Configuration

Microsoft Windows Always On VPN SSL/TLS Certificate Requirements for SSTP

Microsoft Windows Always On VPN SSTP with Let’s Encrypt Certificates

Always On VPN SSTP Certificate Renewal

Windows Server Routing and Remote Access Service (RRAS) is popular for Always On VPN deployments because it supports the Secure Socket Tunneling Protocol (SSTP). The SSTP VPN protocol is recommended for use with the Always On VPN user tunnel because it is firewall friendly. Installing a TLS certificate on the VPN server is necessary to support SSTP VPN connections. Administrators should use a TLS certificate signed by a public certification authority (CA) for optimal reliability and performance.

Click here to view a video demonstration of the procedures outlined in this article.

Certificate Expiration

Of course, all certificates expire, and the TLS certificate used for SSTP is no exception. When using a public TLS certificate, the certificate lifetime is typically no more than one year, which means Always On VPN administrators will be renewing this certificate regularly.

Certificate Renewal

The process of “renewing” an SSTP TLS certificate is essentially the same as installing a new one, as it is best to create a new public/private key pair when renewing a certificate. The following outlines the steps required to generate a Certificate Signing Request (CSR), import the certificate, then assign the certificate to the SSTP listener on the VPN server.

Note: The guidance provided here assumes using an ECC certificate, which is best for optimal security and performance. More details here.

Certificate Request

Open the local computer certificate store (certlm.msc) on the VPN server and perform the following steps to generate a new CSR.

  1. Expand Certificates – Local Computer > Personal.
  2. Right-click the Certificates folder and choose All Tasks > Advanced Operations > Create Custom Request.
  3. Click Next.
  4. Highlight Proceed without enrollment policy.
  5. Click Next.
    1. Select (No template) CNG key from the Template drop-down list.
    2. Select PKCS #10 in the Request format section.
    3. Click Next.
  6. Click on the down arrow next to Details.
    Always On VPN ECDSA SSL Certificate Request for SSTP
  7. Click on the Properties button.
  8. Select the General tab.
    1. Enter the public hostname for the certificate in the Friendly name field.
  9. Select the Subject tab.
    1. Select Common name from the Type drop-down list in the Subject name section.
    2. Enter the public hostname for the certificate in the Value field.
    3. Click Add.
    4. In the Alternative name section, select DNS from the Type drop-down list.
    5. Enter the public hostname for the certificate in the Value field.
    6. Click Add.
      Always On VPN ECDSA SSL Certificate Request for SSTP
  10. Select the Extensions tab.
    1. Expand the Extended Key Usage section.
    2. Select Server Authentication from the Available options section.
    3. Click Add.
      Always On VPN ECDSA SSL Certificate Request for SSTP
  11. Select the Private Key tab.
    1. Expand the Cryptographic Service Provider section.
      1. Uncheck the box next to RSA,Microsoft Software Key Storage Provider.
      2. Check the box next to ECDSA_P256,Microsoft Software Key Storage Provider.
    2. Expand the Key options section.
      1. Check the box next to Make private key exportable.
        Always On VPN ECDSA SSL Certificate Request for SSTP
  12. Click Ok.
  13. Click Next.
  14. Enter a name for the file in the File Name field.
  15. Select Base 64 in the File format section.
  16. Click Finish.

Import Certificate

Once complete, submit the file created to a public CA for signing. When the CA returns the signed certificate, perform the following steps to import it to the local compute certificate store.

  1. Right-click the Certificates folder and choose All Tasks > Import.
  2. Click Next.
  3. Enter the name of the certificate file returned by the public CA in the File name field.
  4. Click Next.
  5. Select Place all certificates in the following store and ensure that Personal is listed in the Certificate store field.
  6. Click Next.
  7. Click Finish.
  8. Click Ok.

Assign Certificate

After importing the new TLS certificate in the local computer’s certificate store, open the Routing and Remote Access management console (rrasmgmt.msc) and perform the following steps to assign the TLS certificate to the SSTP listener.

  1. Right-click the VPN server and choose Properties.
  2. Select the Security tab.
    1. Select the new TLS certificate from the Certificate drop-down list in the SSL Certificate Binding section. When replacing an existing certificate, you may see a certificate with the same name more than once. Click the View button and ensure the new certificate is selected.
    2. Click Ok.
    3. Click Yes to restart the RemoteAccess service.

Demonstration Video

A recorded video demonstration of this process can be found here. The video recording also includes guidance for making these changes on Windows Server Core servers.

Additional Information

Installing or Renewing an SSL/TLS Certificate on Windows Server for Always On VPN and SSTP.

Microsoft Windows Always On VPN SSTP Security Configuration

Microsoft Windows Always On VPN SSL Certificate Requirements for SSTP

Microsoft Windows Always On VPN ECDSA TLS Certificate Request for SSTP

Microsoft Windows Always On VPN SSTP with Let’s Encrypt Certificates

Always On VPN Error 13806

Troubleshooting Always On VPN Error 691 and 812 – Part 2

As a follow-up to my last post regarding Always On VPN error 13801, this post will cover a similar and related error administrators may encounter, the 13806 error. As mentioned previously, certificate configuration is crucial for Always On VPN deployments. I described some specific certificates requirements for IKEv2 in this earlier post. Following this guidance, administrators should have no issues with IKEv2 Always On VPN connections. However, it is always possible to encounter an error if any of these certificates are missing or misconfigured.

Error 13806

Much like the error 13801 described previously, 13806 is also common. When an Always On VPN connection using IKEv2 fails, the Windows Application event log will record an event ID 20227 from the RasClient source. The error message states the following:

“The user [username] dialed a connection named [connection name] which has failed. The error code returned on failure is 13806”.

IKE Failed To Find Valid Machine Certificate

Error 13806 translates to ERROR_IPSEC_IKE_NO_CERT, indicating IKE failed to find a valid machine certificate. The problem can be on the device, the VPN server, or an issue with the VPN server configuration.

Device Certificate

For the device tunnel, the most obvious cause of this error is a missing device authentication certificate on the client itself. Ensure the endpoint has a valid certificate issued by the organization’s internal PKI that includes Client Authentication EKU (OID 1.3.6.1.5.5.7.3.2). The certificate must have a subject name matching the device’s FQDN. It must also be valid (not expired), trusted, and not revoked.

Certificate Chain

A 13806 error will occur if the device certificate installed on the client is not trusted or if the client does not trust the certificate installed on the VPN server. Ensure the client has all the necessary root and intermediate certification authority (CA) certificates installed in their respective certificate stores.

VPN Server Certificate

A 13806 error can also occur if the VPN server does not have a properly configured server certificate. Ensure the VPN server has a valid certificate issued by the organization’s internal PKI that includes both the Server Authentication (OID 1.3.6.1.5.5.7.3.1) and IP security IKE intermediate (OID 1.3.6.1.5.5.8.2.2) EKUs. The subject name must match the public fully qualified domain name (FQDN) used by VPN clients to connect to the VPN server (not the server’s NetBIOS name). Again, ensure the certificate is valid (not expired), trusted, not revoked, and all necessary root and intermediate CA certificates are installed in their respective certificate stores.

Certificate Revocation

An expired Certificate Revocation List (CRL) can also result in a 13801 error. Open the Enterprise PKI console (pkiview.msc) on an issuing CA and review the status of all CRLs. If any are expired, resolve any issues preventing the CRL from publishing successfully, then issue a new CRL by running certutil.exe -crl on the issuing CA server.

RRAS Configuration

Another cause of the 13806 error for the user tunnel is a misconfigured Routing and Remote Access Service (RRAS) VPN server. An error 13806 can happen if the administrator incorrectly defines a trusted root CA using Set-VpnAuthProtocol. Ensure that the root certificate thumbprint matches exactly the root CA server’s thumbprint used to issue certificates to VPN devices and the VPN server.

Get-VpnAuthProtocol

Root CA Certificate Thumbprint

Resolution

Ensure that devices and VPN servers have correctly configured certificates installed. If the root CA certificate is assigned incorrectly on the VPN server, follow the guidelines detailed here to update the configuration.

Additional Information

Microsoft Windows Always On VPN Error 13801

Microsoft Windows Always On VPN Certificate Requirements for IKEv2

Microsoft Windows Always On VPN IPsec Root Certificate Configuration Issue

Microsoft Windows Always On VPN IKEv2 Policy Mismatch Error

Microsoft Windows Always On VPN IKEv2 Security Configuration

Microsoft Windows Always On VPN IKEv2 Fragmentation

Microsoft Windows Always On VPN IKEv2 Load Balancing and NAT

Microsoft Windows Always On VPN IKEv2 Features and Limitations

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