My WCF:
Code:
    [ServiceContract]
    public interface IWorkbookService
    {
        [OperationContract]
        DataTable GetDownpayments(KeyValuePair<int, string> sgm);
    }

    class WorkbookService : IWorkbookService
    {
        public DataTable GetDownpayments(KeyValuePair<int, string> sgm)
        {
            /// works fine, no exceptions here
            return Common.GetDownpayments(selectedSegment);
        }
    }

AS soon as I invoke GetDownpayments() on client side I get:

System.ServiceModel.CommunicationException: The socket connection was aborted. This could be caused by an error processing your message or a receive timeout being exceeded by the remote host, or an underlying network resource issue. Local socket timeout was '00:02:59.8430000'. ---> System.IO.IOException: The read operation failed, see inner exception. ---> System.ServiceModel.CommunicationException: The socket connection was aborted. This could be caused by an error processing your message or a receive timeout being exceeded by the remote host, or an underlying network resource issue. Local socket timeout was '00:02:59.8430000'. ---> System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host
at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags)
at System.ServiceModel.Channels.SocketConnection.ReadCore(Byte[] buffer, Int32 offset, Int32 size, TimeSpan timeout, Boolean closing)
--- End of inner exception stack trace ---
at System.ServiceModel.Channels.SocketConnection.ReadCore(Byte[] buffer, Int32 offset, Int32 size, TimeSpan timeout, Boolean closing)
at System.ServiceModel.Channels.SocketConnection.Read(Byte[] buffer, Int32 offset, Int32 size, TimeSpan timeout)
at System.ServiceModel.Channels.DelegatingConnection.Read(Byte[] buffer, Int32 offset, Int32 size, TimeSpan timeout)
at System.ServiceModel.Channels.ConnectionStream.Read(Byte[] buffer, Int32 offset, Int32 count, TimeSpan timeout)
at System.ServiceModel.Channels.ConnectionStream.Read(Byte[] buffer, Int32 offset, Int32 count)
at System.Net.FixedSizeReader.ReadPacket(Byte[] buffer, Int32 offset, Int32 count)
at System.Net.Security.NegotiateStream.StartFrameHeader(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.NegotiateStream.StartReading(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.NegotiateStream.ProcessRead(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest)
--- End of inner exception stack trace ---
at System.Net.Security.NegotiateStream.ProcessRead(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest)
at System.Net.Security.NegotiateStream.Read(Byte[] buffer, Int32 offset, Int32 count)
at System.ServiceModel.Channels.StreamConnection.Read(Byte[] buffer, Int32 offset, Int32 size, TimeSpan timeout)
--- End of inner exception stack trace ---

Server stack trace:
at System.ServiceModel.Channels.StreamConnection.Read(Byte[] buffer, Int32 offset, Int32 size, TimeSpan timeout)
at System.ServiceModel.Channels.SessionConnectionReader.Receive(TimeSpan timeout)
at System.ServiceModel.Channels.SynchronizedMessageSource.Receive(TimeSpan timeout)
at System.ServiceModel.Channels.FramingDuplexSessionChannel.Receive(TimeSpan timeout)
at System.ServiceModel.Channels.FramingDuplexSessionChannel.TryReceive(TimeSpan timeout, Message& message)
at System.ServiceModel.Dispatcher.DuplexChannelBinder.Request(Message message, TimeSpan timeout)
at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout)
at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs)
at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation)
at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message)

Exception rethrown at [0]:
at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
at DSSIP_Test.ServiceReference1.IWorkbookService.GetDownpayments(KeyValuePair`2 selectedSegment)
at DSSIP_Test.ServiceReference1.WorkbookServiceClient.GetDownpayments(KeyValuePair`2 selectedSegment) in C:\PRJ\DSSIP_Test\Service References\ServiceReference1\Reference.cs:line 205
There's nothing wrong with timeout, that's fo sure. Table to be returned is rather small - about 10 rows with 20 values in each. All other functions in IWorkbookService work flawlessly, even with much more size of transferred data.

What's wrong to my code?