Connecting to WCF Rest Service Application from powershell not working as expected

Question

I have a WCF service application set up so when I call the address it just returns true.

IRemoteService.cs

     [OperationContract]
            [WebInvoke(Method = "GET", ResponseFormat = WebMessageFormat.Json,
               BodyStyle = WebMessageBodyStyle.Wrapped,
               UriTemplate = "ValidationResult/")]
            bool ValidationResult();

RemoteService.svc.cs

namespace RemoteService
{    
    public class RemoteService : IRemoteService
    {
        public bool ValidationResult()
        {
            return true;
            //throw new NotImplementedException();
        }
    }
}

I have added an application on IIS and now I can access the service on the following url :

https://localhost/ValidationServiceApp/RemoteService.svc/validationresult/

This returns :

{"ValidationResultResult":true}

Works great. But when I run the following powershell script, I cant access the service :

$url = "https://localhost/ValidationServiceApp/SASRemoteService.svc/validationresult/"
$result = Invoke-RestMethod -Method GET -Uri $url 
Write-Host $result

I must point out, I have tried on a client application called 'I'm only resting' and this returns whats expected. So I think it must be something to do with powershell. Either I haven't allowed something in the web.config file or some setting missing in powershell. I have also tried to ignore certificate errors on powershell. This didn't help.

Error from powershell :

Invoke-RestMethod : The underlying connection was closed: An unexpected error occurred on a send.
At line:18 char:11
+ $result = Invoke-RestMethod -Method GET -Uri $url
+           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (System.Net.HttpWebRequest:HttpWebRequest) [Invoke-RestMethod], WebException
    + FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeRestMethodCommand

Here is the web.config file for the service :

<?xml version="1.0"?>
<configuration>

  <appSettings>
    <add key="aspnet:UseTaskFriendlySynchronizationContext" value="true"/>
  </appSettings>
  <system.web>
    <compilation debug="true" targetFramework="4.6"/>
    <httpRuntime targetFramework="4.6"/>
    <httpModules>
      <add name="ApplicationInsightsWebTracking" type="Microsoft.ApplicationInsights.Web.ApplicationInsightsHttpModule, Microsoft.AI.Web"/>
    </httpModules>
  </system.web>
  <system.serviceModel>
    <bindings>
      <webHttpBinding>    
        <binding name="webHttpTransportSecurity">
          <security mode="Transport">
            <transport clientCredentialType="None" proxyCredentialType="None" />
          </security>
        </binding>
      </webHttpBinding>
    </bindings>
    <services>
      <service name="RemoteService.RemoteService" behaviorConfiguration="ServiceBehaviour">

        <endpoint address ="" 
                  binding="webHttpBinding" 
                  contract="RemoteService.IRemoteService" 
                  bindingConfiguration="webHttpTransportSecurity" 
                  behaviorConfiguration="web" />

        <endpoint address="mex"
                   binding="mexHttpsBinding"
                   contract="IMetadataExchange" />        

      </service>
    </services>
    <behaviors>
      <serviceBehaviors>
        <behavior name="ServiceBehaviour">
          <!-- To avoid disclosing metadata information, set the values below to false before deployment -->
          <serviceMetadata httpGetEnabled="false" httpsGetEnabled="true"/>
          <!-- To receive exception details in faults for debugging purposes, set the value below to true.  Set to false before deployment to avoid disclosing exception information -->
          <serviceDebug includeExceptionDetailInFaults="false"/>

        </behavior>
      </serviceBehaviors>
      <endpointBehaviors>
        <behavior name="web">
          <webHttp/>
        </behavior>
      </endpointBehaviors>
    </behaviors>
    <protocolMapping>

      <add binding="webHttpBinding" scheme="https"/>
    </protocolMapping>    
    <serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true"/>
  </system.serviceModel>
  <system.webServer>
    <modules runAllManagedModulesForAllRequests="true">
      <remove name="ApplicationInsightsWebTracking"/>
      <add name="ApplicationInsightsWebTracking" type="Microsoft.ApplicationInsights.Web.ApplicationInsightsHttpModule, Microsoft.AI.Web"
        preCondition="managedHandler"/>
    </modules>
    <!--
        To browse web app root directory during debugging, set the value below to true.
        Set to false before deployment to avoid disclosing web app folder information.
      -->
    <directoryBrowse enabled="true"/>
    <validation validateIntegratedModeConfiguration="false"/>
  </system.webServer>

</configuration>

Answer 1

Managed to find the problem.

I needed to edit permissions on the hosted service in IIS. So I added Users ({pcname}/Users) to the list of allowed users.

I would delete the question, but perhaps this may help someone in the future :)