Power BI Report server - Issue with deploying power bi report

I am having a very similar issue.  

I can successfully upload a Report Builder report, however am unable to upload a Power BI report both through Power BI Desktop (SSRS) and from the Upload button on the Power BI Reporting Server.

I do receive the following in the logs however....

2017-05-30 13:13:14.3514|FATAL|1|Could not start PBIXSystem.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.Net.HttpListenerException: Access is denied
at System.Net.HttpListener.AddAllPrefixes()
at System.Net.HttpListener.Start()
at Microsoft.Owin.Host.HttpListener.OwinHttpListener.Start(HttpListener listener, Func`2 appFunc, IList`1 addresses, IDictionary`2 capabilities, Func`2 loggerFactory)
at Microsoft.Owin.Host.HttpListener.OwinServerFactory.Create(Func`2 app, IDictionary`2 properties)
--- End of inner exception stack trace ---
at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at Microsoft.Owin.Hosting.ServerFactory.ServerFactoryAdapter.Create(IAppBuilder builder)
at Microsoft.Owin.Hosting.Engine.HostingEngine.Start(StartContext context)
at Microsoft.PowerBI.ReportServer.WebHost.Program.Main()

Thanks for any assistance you can provide!

Aaron G.