Windows Error Fix: WinRM Certificate Subject Filters Without Issuers

Error Description

The error "The WinRM client cannot process the request because client certificate subject filters were specified without any issuers." happens during remote Windows Management (WinRM) or PowerShell sessions. It appears when your client machine forces certificate-based authentication but the WinRM client configuration contains a matching subject filter rule that lacks a corresponding certificate authority (CA) issuer thumbprint.

By security design, Windows prevents WinRM from executing requests using a Subject filter unless it can also restrict authentication to a known, valid issuing certificate authority. This mismatch breaks the secure handshake and halts the connection entirely.

Step-by-Step Fix

Follow these steps on the client machine experiencing the error to correct the configuration.

Step 1: Open PowerShell as Administrator

1. Press the Windows Key on your keyboard.
2. Type PowerShell into the search bar.
3. Right-click on Windows PowerShell from the list.
4. Select Run as administrator.

Step 2: Check Existing Client Certificate Filters

Run this command to inspect your current WSMan configuration entries:

Get-ChildItem -Path WSMan:\localhost\ClientCertificate

Locate any configured entries that show a Subject property but have a blank or missing Issuer property.

Step 3: Remove the Faulty Configuration Entry

Clear out the incorrect configuration completely so you can rebuild it safely. Run the following command (replace {ItemName} with the specific item identifier or index found in Step 2, often named ClientCertificate or structured as an index like 1, 2):

Remove-Item -Path WSMan:\localhost\ClientCertificate\{ItemName} -Force

Note: If you want to clear all client certificate mappings to start fresh, you can use:

Get-ChildItem -Path WSMan:\localhost\ClientCertificate | Remove-Item -Force

Step 4: Find the Correct Certificate Issuer Thumbprint

You need the thumbprint of the Root or Intermediate Certificate Authority (CA) that generated your user certificate.

1. Run this command to see your personal certificates:

   Get-ChildItem -Path Cert:\LocalMachine\My

2. Locate the certificate you use for authentication.
3. Note the Thumbprint of the certificate issuer. You can view the issuer thumbprint by executing:

   (Get-ChildItem -Path Cert:\LocalMachine\My\{YourCertThumbprint}).Issuer

Step 5: Re-create the Mapping with both Subject and Issuer

Run this command to create a valid mapping configuration, making sure to include the -Issuer parameter:

\$MappingParameters = @{
    Path       = 'WSMan:\localhost\ClientCertificate'
    Subject    = 'your user principal name@domain.com'
    URI        = '*'
    Issuer     = 'INSERT ISSUER THUMBPRINT HERE'
    Credential = (Get-Credential)
    Force      = \$true
}
New-Item @MappingParameters

1. Replace your user principal name@domain.com with your exact certificate Subject/UPN string.
2. Replace INSERT ISSUER THUMBPRINT HERE with the actual SHA-1 thumbprint string found in Step 4.
3. Provide your account credentials when prompted by the secure popup.

Step 6: Restart the WinRM Service