Microsoft Intune Certificate Connector Failure

The Microsoft Intune Certificate Connector enables the provisioning and de-provisioning of on-premises PKI certificates for Intune-managed devices. Always On VPN administrators using Intune to deploy certificates with the Intune Certificate Connector using either PKCS or SCEP may encounter a scenario where certificates are no longer being provisioned to users or devices after working reliably previously.

Certificate Not Found

When this issue occurs, users will no longer be able to access the VPN and receive a “certificate could not be found that can be used with this Extensible Authentication Protocol” error message.

Connector Status

To determine the status of the Intune Certificate Connector, open the Microsoft Intune Admin Center (https://intune.microsoft.com) and navigate to Tenant Administration > Connectors and Tokens > Certificate Connectors. The status of the certificate connector server will be in Error.

Event Log

Open the event log on the server where the Intune Certificate Connector is installed. Navigate to Applications and Services Logs > Microsoft > Intune > CertificateConnectors > Operational. Here, you will find a variety of warning and error messages.

Event ID 5001

This is a warning from the CertificateConnectors source with event ID 5001 in the Task Category HealthMessageUploadFailedAttempt with the following details.

PKI Create Service:

Failed to upload health messages. Requeuing messages.

Event ID 1003

This is an error from the CertificateConnectors source with event ID 1003 in the Task Category PkcsDownloadFailure with the following details.

PKI Create Service:

Failed to download PKCS requests.

Event ID 2

This is an error from the CertificateConnectors source with event ID 2 in the Task Category Exception with the following details.

PKI Create Service:

Microsoft.Intune.Connectors.PkiCreateProcessor.Process threw an exception.

Expired Certificate

The warning and error messages recorded in the event log indicate an expired certificate on the Intune Certificate Connector server. Open the local computer certificate store (certlm.msc) on the server where the Intune Certificate Connector is installed. Review the expiration date of the certificate issued by Microsoft Intune ImportPFX Connector CA. It is most likely expired.

Click on the Certification Path tab to view the certificate status.

Renew Certificate

To renew this certificate, you must reinstall the Intune Certificate Connector. However, you do not have to uninstall it first. To renew the certificate, navigate to C:\Program Files\Microsoft Intune\PFXCertificateConnector\ConnectorUI and double-click on PFXCertificateConnectorUI.exe. Follow the prompts without making changes to the existing configuration. You’ll be prompted for the service account password (if using a domain account) and proxy credentials (if using a proxy server). In addition, you’ll be asked to sign in to Entra ID (formerly Azure AD). Be sure to provide credentials that are a global administrator and have an Intune license assigned. Once the process is complete, a new certificate will be installed in the local computer certificate store.

Intune Configuration

After updating the Intune Certificate Connector, a new certificate connector appears in the Intune Admin Center. You can now safely delete the old connector and rename the new one accordingly.

Redundancy

Deploying multiple instances of the Intune Certificate Connector is an excellent way to avoid future outages! It’s also a good idea to stagger their installation by a few months to ensure that a future certificate expiration doesn’t result in lost functionality. If you’ve deployed Intune Certificate Connectors recently, consider updating them at rotating intervals so certificates expire at different times.

Additional Information

Intune Certificate Connector Configuration Failed

Intune Certificate Connector Service Account and PKCS

Intune Certificate Connector Configuration Failure

Microsoft Intune Learning Resources for Always On VPN Administrators

Always On VPN at MMSMOA 2023

I’m excited to share that I’ve been invited to present at the popular Midwest Management Summit at Mall of America (MMSMOA) this year! The event takes place Monday, May 2, through Thursday, May 4, 2023.

Sessions

I will be delivering two talks at the event this year. One on Microsoft Always On VPN and Intune, the other on deploying certificate using Intune.

Always On VPN and Intune: Notes from the FieldTuesday, May 2 at 10:00 AM CDT

This session will cover all aspects of deploying and managing Always On VPN client configuration settings using Microsoft Intune.

Intune Certificate ManagementWednesday, May 3 at 10:00 AM CDT

This session will provide detailed configuration guidance and best practice recommendations for issuing on-premises enterprise PKI certificate using Microsoft Intune.

Attending MMS?

Will you be attending MMSMOA? Let’s connect! Drop in on my sessions, of course, but let’s plan to hang out! I will have copies of my book to give away too, so don’t miss out. Send me a note here or on Twitter, or just find me at the conference. Looking forward to seeing all of you soon!

Always On VPN and Device Sharing

Always On VPN client configuration settings are typically deployed in the user’s context. However, this presents a unique challenge when sharing a single device with multiple users who have an Always On VPN profile assigned to them. By design, Windows designates only a single user profile on a shared device to be “always on”. When multiple users with assigned Always On VPN profiles share the same machine, it could yield unexpected results.

Auto Trigger Profile

When an Always On VPN profile is provisioned to a user, Windows records information about this profile in the registry. Specifically, the Always On VPN profile’s name and GUID are recorded, as well as the user’s Security Identifier (SID) and the path to the rasphone.pbk file that contains the Always On VPN profile.

Multiple Users

When a new user logs on to a shared device and receives their Always On VPN profile, Windows overwrites this existing data in the registry with the current user’s information. Each time this user logs on, their Always On VPN connection will establish automatically. Any other users with Always On VPN profiles configured on the same shared device will no longer connect automatically after this. The most recently deployed Always On VPN profile will be designated the “always on” profile.

Connect Automatically

In the above scenario, any user with an assigned Always On VPN profile on the shared device can take over the “always on” designation by opening the VPN connection properties and checking the “Connect automatically” check box.

When this happens, this user will now own the “always on” profile, and other users on the shared device will no longer connect automatically.

Workarounds

If multiple users share a single device requiring Always On VPN connectivity, you have a few options.

Intune

If you are deploying Always On VPN client configuration settings using Intune, you must use the Custom device configuration profile template. Specifically, as shown here, you must deploy your XML configuration file using the ./Device/Vendor/MSFT/VPNv2/ OMA-DM URI.

Unfortunately, the native Intune VPN template does not support deploying Always On VPN profiles in the “all users” context.

PowerShell

When using PowerShell, either natively or with SCCM or another software deployment tool, administrators can use my Always On VPN deployment PowerShell script with the -AllUserConnection parameter.

PowerON DPC

When using PowerON Platforms’ Dynamic Profile Configurator (DPC) to deploy Always On VPN client configuration settings using on-premises Active Directory or via Intune, no changes are required. DPC deploys Always On VPN user profiles in the “all users” context by default.

Additional Information

New-AovpnConnection.ps1 PowerShell Script on GitHub

PowerON Platforms’ Dynamic Profile Configurator (DPC)

Always On VPN DPC with PowerON Platforms’ DPC