Always On VPN Error 13868

Troubleshooting Always On VPN Error 691 and 812 – Part 2

The Internet Key Exchange version 2 (IKEv2) VPN protocol is the protocol of choice for Microsoft Always On VPN deployments where the highest levels of security and assurance are required. However, as I’ve written about in the past, often the default IKEv2 security settings are less than desirable. Before using IKEv2 VPN in a production environment the administrator will need to update these security settings accordingly.

Connection Failure

When configuring Windows Server Routing and Remote Access Service (RRAS) or a third-party VPN appliance to support IKEv2 using custom security policies, the administrator may encounter a scenario in which a connection cannot be established due to a policy mismatch error. When the connection attempt fails, an error will be recorded in the Windows Application event log from the RasClient source with Event ID 20227. 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 13868.”

Always On VPN IKEv2 Policy Mismatch Error

Error Code 13868

Error code 13868 translates to ERROR_IPSEC_IKE_POLICY_MATCH. Essentially this error indicates that the IKEv2 security policy on the client did not match the configuration on the server.

Server Configuration

To view the current IKEv2 IPsec policy configuration, open an elevated PowerShell command window and run the following command.

Get-VpnServerIPsecConfiguration

Always On VPN IKEv2 Policy Mismatch Error

Client Configuration

To ensure interoperability, the VPN client must be configured to use the same IKEv2 security policy as defined on the sever. To view a VPN client’s currently configured IKEv2 security policy, open an elevated PowerShell command window and run the following command.

Get-VpnConnection -Name [connection name] | Select-Object -ExpandProperty IPsecCustomPolicy

Always On VPN IKEv2 Policy Mismatch Error

Note: If this PowerShell command returns no output, the VPN connection is not using a custom IKEv2 IPsec security policy.

Updating Settings

Guidance for configuring IKEv2 security policies on Windows Server RRAS and Windows 10 can be found here.

NPS Policy

Another common cause of IKEv2 policy mismatch errors is a misconfigured Network Policy Server (NPS) network policy. Specifically, administrators may disable Basic and Strong encryption for MPPE in an attempt to improve security.

Always On VPN IKEv2 Policy Mismatch Error

The NPS policy for Always On VPN must include Strong encryption at a minimum. Basic and No encryption can be safely disabled.

Always On VPN IKEv2 Policy Mismatch Error

Summary

IKEv2 policy mismatch errors can be resolved easily by ensuring both the VPN server and client are configured to use the same IPsec security policies. Use the PowerShell commands in the above referenced above to validate settings and make changes when necessary.

Additional Information

Microsoft Always On VPN Error 13801

Microsoft Windows Always On VPN Error 13806

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

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 PowerShell Script Issues in Windows 11

Many administrators are now beginning to test Always On VPN functionality on the latest Microsoft Windows client operating system, Windows 11. Initially, Microsoft had some issues with provisioning and managing Always On VPN profiles on Windows 11 using Microsoft Endpoint Manager/Intune, but those have been resolved. However, some lingering problems may delay enterprise deployments of Always On VPN on Windows 11 for some organizations, specifically those using PowerShell with Active Directory group policy startup scripts or System Center Configuration Manager (SCCM).

Important Note: The issues outlined in this article have been resolved! The fix for the WMI enumeration bug is addressed in the following updates:

Windows 11 21H2 – KB5022905 (build 22000.1641)

Windows 11 22H2 – KB5026446 (build 22621.1778)

MakeProfile.ps1

Microsoft has published guidance for deploying Always On VPN profiles using PowerShell with their MakeProfile.ps1 script. This script extracts configuration details from a template VPN profile to create another PowerShell script called VPN_Profile.ps1, which is used to create the Always On VPN profile. SCCM administrators commonly use VPN_Proifle.ps1 to deploy Always On VPN profiles. However, running this script on Windows 11 fails and returns the following error message.

“Unable to create [VPN profile name] profile: A general error occurred that is not covered by a more specific code.”

This issue appears to be related to a problem with the WMI-to-CSP bridge, specifically enumerating the MDM_VPNv2_01 class in the root\cimv2\mdm\dmmap namespace. Here you can see the template VPN profile with PowerShell and Get-VpnConnection.

However, attempts to view the MDM_VPNv2_01 class of this VPN profile using PowerShell and Get-CimInstance fail.

New-AovpnConnection.ps1

Interestingly, administrators may find that my Always On VPN PowerShell deployment script works more reliably on Windows 11, although not always. In my experience, I’ve found that it sometimes fails once (profile is loaded, but the configuration is incomplete), then works after deleting the profile and creating it again. If the Microsoft-provided script isn’t working, give mine a try and see if it works better for you.

Note: When deploying Always On VPN profiles using my PowerShell deployment script via Active Directory startup scripts, it seems to fail consistently for some reason. Go figure. 😉

Remove-AovpnConnection.ps1

The issues described previously with Windows 11 are also negatively affecting some of my other PowerShell scripts. For example, running Remove-Aovpnconnection.ps1 on Windows 11 fails and returns the following error message.

“A general error occurred that is not covered by a more specific error code.”

Current Status

Microsoft is currently aware of this issue. However, I am aware of no timeframe for resolution at the time of this writing. Hopefully, Microsoft addresses this soon so organizations can move forward with their Windows 11 migration projects.

Additional Information

Microsoft Windows Always On VPN Windows 11 Issues with Microsoft Endpoint Manager/Intune

Microsoft Windows Always On VPN Profile Deployment Script

Microsoft Windows Always On VPN Remove Always On VPN Profile Script

Always On VPN PowerShell Script Repository on GitHub

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