CRM C# - Custom Workflow Activity - Input Arguments - EntityReference
<p>I'm Making a custom worflow activity, which is in the process . I have two inputs that are EntityReference . When I test the code appears me an error referenced to these two inputs , as shown in the figure:
<a href="https://i.stack.imgur.com/PxdMu.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/PxdMu.png" alt="enter image description here"></a>
I have a trace at the beginning of the try, but not being shown .
There ir my code:</p>

<pre><code> public class WK_DecorrerObjetivo : CodeActivity
{
    [Input("Alvo")]
    [ReferenceTarget("xpto_alvo")]
    public InArgument&lt;EntityReference&gt; alvo { get; set; }

    [Input("Actividade do Objetivo")]
    [ReferenceTarget("xpto_atividadedeobjetivo")]
    public InArgument&lt;EntityReference&gt; atividadeObjetivo { get; set; }

    protected override void Execute(CodeActivityContext Execontext)
    {

        ITracingService _tracing;
        IWorkflowContext context = null;
        IOrganizationServiceFactory serviceFactory = null;
        IOrganizationService service = null;  
        OrganizationServiceContext serviceContext = null;

        try
        {
            #region Get Work Flow Context

            context = Execontext.GetExtension&lt;IWorkflowContext&gt;();
            serviceFactory = Execontext.GetExtension&lt;IOrganizationServiceFactory&gt;();
            service = serviceFactory.CreateOrganizationService(context.InitiatingUserId);
            serviceContext = new OrganizationServiceContext(service);

            _tracing = Execontext.GetExtension&lt;ITracingService&gt;();
            _tracing.Trace("Here");
            EntityReference alvoRef = alvo.Get(Execontext);
            EntityReference atividadeObjetivoRef = atividadeObjetivo.Get(Execontext);
          }
          catch() {}
       }
</code></pre>

<p>Can anyone help?</p>