HTTPS Certificate Not Found

HTTPS Certificate Not Found

Version: Any
After configuration the certificate for your PowerShell Universal and attempting to start the server, you receive the following error. 

Unhandled exception. System.InvalidOperationException: The requested certificate could not be found in LocalMachine/My with AllowInvalid setting: False.
at Microsoft.AspNetCore.Server.Kestrel.Https.CertificateLoader.LoadFromStoreCert(String subject, String storeName, StoreLocation storeLocation, Boolean allowInvalid)
at Microsoft.AspNetCore.Server.Kestrel.KestrelConfigurationLoader.LoadFromStoreCert(CertificateConfig certInfo)
at Microsoft.AspNetCore.Server.Kestrel.KestrelConfigurationLoader.LoadCertificate(CertificateConfig certInfo, String endpointName)
at Microsoft.AspNetCore.Server.Kestrel.KestrelConfigurationLoader.Load()
at Microsoft.AspNetCore.Server.Kestrel.Core.KestrelServer.ValidateOptions()
at Microsoft.AspNetCore.Server.Kestrel.Core.KestrelServer.StartAsync[TContext](IHttpApplication`1 application, CancellationToken cancellationToken)
at Microsoft.AspNetCore.Hosting.GenericWebHostService.StartAsync(CancellationToken cancellationToken)
at Microsoft.Extensions.Hosting.Internal.Host.StartAsync(CancellationToken cancellationToken)
at Microsoft.Extensions.Hosting.HostingAbstractionsHostExtensions.RunAsync(IHost host, CancellationToken token)
at Microsoft.Extensions.Hosting.HostingAbstractionsHostExtensions.RunAsync(IHost host, CancellationToken token)
at Microsoft.Extensions.Hosting.HostingAbstractionsHostExtensions.Run(IHost host)
at Universal.Server.Program.Main(String[] args) in D:\a\universal\universal\src\Universal.Server\Program.cs:line 31
The certificate is correctly returned by PowerShell.
Get-ChildItem Cert:\LocalMachine\My
Root Cause:
The root cause of the issue is that the ASP.NET Core certificate location code is different than PowerShell. 
When specifying the certificate, do not use the fully qualified subject name. Rather, use the portion after CN=. For example, if PowerShell shows the subject name of my certificate as CN=localhost, then I would enter localhost in to appsettings.json. 
We have created a PowerShell script you can use to determine whether your certificate can be found by the web host. Enter your subject name in the variable below and run the script. 
$allowInvalid = $true
$subject = 'localhost'
$store = [System.Security.Cryptography.X509Certificates.X509Store]::new('My', 'LocalMachine')

$storeCertificates = $store.Certificates;
$foundCertificates = $storeCertificates.Find('FindBySubjectName', $Subject, $allowInvalid);

function Test-IsCertificateAllowedForServerAuth

    $ServerAuthenticationOid = "";
    $result = $false 

    foreach($cert in $foundCertificates)
        if ($cert.Extensions)
            foreach($extension in $cert.Extensions  | Where-Object { $_ -is [System.Security.Cryptography.X509Certificates.X509EnhancedKeyUsageExtension] })
                $result = $true
                foreach ($oid in $extension.EnhancedKeyUsages)
                    if ($oid.Value -eq $ServerAuthenticationOid)
                        return $true;
    -not $result

$foundCertificates | Where-Object { (Test-IsCertificateAllowedForServerAuth $_) -and $_.HasPrivateKey  }

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