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import-bot (20211) [Avatar] Offline
[Originally posted by bogatiy2]

When I run with HTTP with this example, I get the following error on the
client console:

Unhandled Exception: System.Runtime.Remoting.RemotingException: Invalid SOAPActi
on specified:

Server stack trace:
at System.Runtime.Remoting.Channels.SoapServerFormatterSink.ProcessMessage(IS
erverChannelSinkStack sinkStack, IMessage requestMsg, ITransportHeaders requestH
eaders, Stream requestStream, IMessage& responseMsg, ITransportHeaders& response
Headers, Stream& responseStream)

Exception rethrown at [0]:
at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage req
Msg, IMessage retMsg)
at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgDa
ta, Int32 type)
at HelloObj.Greet(String name)
at HelloClient.Main(String[] args) in c:helloclientclienthello.cs:line 22
Press any key to continue

The file contents of helloclient.cs (I renamed it to clienthello.cs) is:

using System;
using System.Runtime.Remoting;
using System.Runtime.Remoting.Channels;
using System.Runtime.Remoting.Channels.Http;

class HelloClient
public static void Main(string[] args)
ChannelServices.RegisterChannel(new HttpChannel());
HelloObj helloObjRef = (HelloObj)Activator.GetObject(
Console.WriteLine(helloObjRef.Greet("Joe Bloggs"));
Console.WriteLine(helloObjRef.Greet("Mary Bloggs"));
public interface HelloObj
string Greet(string name);

I added the interface so get the client to compile on VS. It works great with

On the server window, the object activates and then hangs, the output is:

Csmilieocuments and Settingsuser1DesktopgrimesDotNetExamplescha_5>helloservice
configuring remoting...
waiting for remote calls...
hit ENTER to exit...
HelloObj activated...

The contents of the helloservice.cs file is:

using System;
using System.Runtime.Remoting;

public class HelloObj : MarshalByRefObject {

public HelloObj() {
Console.WriteLine("HelloObj activated...");

public string Greet(string name) {
lock(this) { numGreet++; }
string greeting = "Hello, " + name + "!";
Console.WriteLine("greeting #{0}: " + greeting, numGreet);
return greeting;

private int numGreet = 0;

public class HelloService {
public static void Main(string[] args) {

Console.WriteLine("configuring remoting...");
string configFile = "helloservice.exe.http.singleton.config";
if (args.Length > 0) configFile = args[0];
Console.WriteLine("configFile=" + configFile);

Console.WriteLine("waiting for remote calls...");
Console.WriteLine("hit ENTER to exit...");

The contents of the config file is:

type="HelloObj, HelloService"
<!--channel<br /> type="System.Runtime.Remoting.Channels.Http.HttpChannel,<br /> System.Runtime.Remoting"<br /> port="6789"<br /> /-->

Why is this exception being thrown?
import-bot (20211) [Avatar] Offline
Re: Remoting 5.3.3 example
[Originally posted by fgrimes]


I hope I don't offend if I offer my own personal approach to
finding errors like this...

You say you changed the original working example, by renaming (and ?).
Since the original worked ok, I would start from scratch with the
example verbatim from the book and trace my changes one-by-one from
there. It's often quicker, and always more informative, than looking
for typos.