NullReferenceException when running WCF service in Visual Studio using WCF Test Client

Question

I have created a very simple project using the WCF Class Library template and now I'm trying to run it in Visual Studio. There's no compilation error, but when the WCF Test Client window opens I get this dialog with an Exception and I can't understand whats going on:

Here is the full description of the Exception:

************** Exception Text **************
System.NullReferenceException: Object reference not set to an instance of an object.
   at Microsoft.Tools.Common.SdkPathUtility.GetRegistryValue(String registryPath, String registryValueName)
   at Microsoft.Tools.Common.SdkPathUtility.GetSdkPath(Version targetFrameworkVersion)
   at Microsoft.Tools.TestClient.ToolingEnvironment.get_MetadataTool()
   at Microsoft.Tools.TestClient.ServiceAnalyzer.GenerateProxyAndConfig(String projectPath, String address, String configPath, String proxyPath, Int32 startProgressPosition, Int32 endProgressPostition, BackgroundWorker addServiceWorker, String& errorMessage)
   at Microsoft.Tools.TestClient.ServiceAnalyzer.AnalyzeService(String address, BackgroundWorker addServiceWorker, Single startProgress, Single progressRange, String& errorMessage)
   at Microsoft.Tools.TestClient.Workspace.AddServiceProject(String endpoint, BackgroundWorker addServiceWorker, Single startProgress, Single progressRange, String& error)
   at Microsoft.Tools.TestClient.AddServiceExecutor.Execute(AddServiceInputs inputs, Workspace workspace, BackgroundWorker addServiceWorker)
   at Microsoft.Tools.TestClient.UI.MainForm.addServiceWorker_DoWork(Object sender, DoWorkEventArgs e)
   at System.ComponentModel.BackgroundWorker.OnDoWork(DoWorkEventArgs e)
   at System.ComponentModel.BackgroundWorker.WorkerThreadStart(Object argument)


************** Loaded Assemblies **************
mscorlib
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.34209 built by: FX452RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/mscorlib.dll
----------------------------------------
WcfTestClient
    Assembly Version: 12.0.0.0
    Win32 Version: 12.0.21005.1 built by: REL
    CodeBase: file:///C:/Program%20Files%20(x86)/Microsoft%20Visual%20Studio%2012.0/Common7/IDE/WcfTestClient.exe
----------------------------------------
System
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.34239 built by: FX452RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System/v4.0_4.0.0.0__b77a5c561934e089/System.dll
----------------------------------------
System.Windows.Forms
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.34209 built by: FX452RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Windows.Forms/v4.0_4.0.0.0__b77a5c561934e089/System.Windows.Forms.dll
----------------------------------------
System.Drawing
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.34209 built by: FX452RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Drawing/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll
----------------------------------------
System.Configuration
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.34209 built by: FX452RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Configuration/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll
----------------------------------------
System.Xml
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.34230 built by: FX452RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Xml/v4.0_4.0.0.0__b77a5c561934e089/System.Xml.dll
----------------------------------------
System.ServiceModel
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.34230 built by: FX452RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.ServiceModel/v4.0_4.0.0.0__b77a5c561934e089/System.ServiceModel.dll
----------------------------------------
System.Core
    Assembly Version: 4.0.0.0
    Win32 Version: 4.0.30319.34209 built by: FX452RTMGDR
    CodeBase: file:///C:/Windows/Microsoft.Net/assembly/GAC_MSIL/System.Core/v4.0_4.0.0.0__b77a5c561934e089/System.Core.dll
----------------------------------------

I have only two files in my project, IProductService:

namespace LayerNorthwindService
{
    // NOTE: You can use the "Rename" command on the "Refactor" menu to change the interface name "IService1" in both code and config file together.
    [ServiceContract]
    public interface IProductService
    {
        [OperationContract]
        Product GetProduct(int id);

        [OperationContract]
        bool UpdateProduct(Product product, ref string message);

        // TODO: Add your service operations here
    }

    // Use a data contract as illustrated in the sample below to add composite types to service operations.
    // You can add XSD files into the project. After building the project, you can directly use the data types defined there, with the namespace "LayerNorthwindService.ContractType".
    [DataContract]
    public class Product
    {
        [DataMember]
        public int ProductID { get; set; }
        [DataMember]
        public string ProductName { get; set; }
        [DataMember]
        public string QuantityPerUnit { get; set; }
        [DataMember]
        public decimal UnitPrice { get; set; }
        [DataMember]
        public bool Discontinued { get; set; }
    }
}

And ProductService:

namespace LayerNorthwindService
{
    // NOTE: You can use the "Rename" command on the "Refactor" menu to change the class name "Service1" in both code and config file together.
    public class ProductService : IProductService
    {
        public Product GetProduct(int id)
        {
            var product = new Product();
            product.ProductID = id;
            product.ProductName = "Product name";
            product.UnitPrice = 10.0m;
            product.QuantityPerUnit = "fake QPU";
            return product;
        }

        public bool UpdateProduct(Product product, ref string message)
        {
            var result = true;

            if (product.UnitPrice <= 0)
            {
                message = "Prince cannot be <= 0";
                result = false;
            }
            else if (string.IsNullOrEmpty(product.ProductName))
            {
                message = "product name cannot be empty";
                result = false;
            }
            else if (string.IsNullOrEmpty(product.QuantityPerUnit))
            {
                message = "QPU cannot be empty";
                result = false;
            }
            else
            {
                message = "product updated successfully";
                result = true;
            }

            return result;
        }
    }
}

Answer 1

I solved my problem by doing what is said on this question's accepted answer: Unable to add service in WcfTestClient when copy to a different machine

As I'm using Windows 8.1, I've installed Windows SDK for Windows 8.1 and everything works fine now.

If you are going to install it on your machine, pay attention to the version of the SDK you're installing. There is a correct version for each Windows version.