IBM MQ .Net Client v9.1.4 cannot connect to MQ server 8.0.0.4 CompCode: 2 Reason: 2059

This is excerpt of program which throws an exception with code MQException (CompCode: 2 Reason: 2059)

                Hashtable properties = new Hashtable();

                properties.Add(MQC.TRANSPORT_PROPERTY, MQC.TRANSPORT_MQSERIES_MANAGED);
                properties.Add(MQC.HOST_NAME_PROPERTY, _host);
                properties.Add(MQC.PORT_PROPERTY, _port);
                properties.Add(MQC.CHANNEL_PROPERTY, _channel);

               _mqQMgr = new MQQueueManager(_manager, properties);

I have setup trace log which produces link. Small excerpt of it :

000002B4 14:45:52.635100   16832.1      0x00000000 0B 08 00 00                                     : ..
000002B5 14:45:52.635100   16832.1    ----}  MQFAP.NmqiConnect(String,NmqiConnectOptions,MQConnectOptions,Hconn,Phconn,out int,out int,ManagedHconn) rc=OK
000002B6 14:45:52.636100   16832.1     System.ArgumentNullException: Value cannot be null.
Parameter name: dest
   at System.Array.Copy(Array sourceArray, Int32 sourceIndex, Array destinationArray, Int32 destinationIndex, Int32 length, Boolean reliable)
   at System.Array.CopyTo(Array array, Int32 index)
   at IBM.WMQ.MQFAPMQCNO.set_ConnTag(Byte[] value)
   at IBM.WMQ.MQFAP.NmqiConnect(String name, NmqiConnectOptions pNmqiConnectOpts, MQConnectOptions cno, Hconn remoteParentHconn, Phconn pHconn, Int32& compCode, Int32& reason, ManagedHconn rcnHconn)
   at IBM.WMQ.MQFAP.MQCONNX(String pQMgrName, MQConnectOptions pConnectOpts, Phconn phconn, Int32& pCompCode, Int32& pReason)
000002B7 14:45:52.636100   16832.1    ---}  MQFAP.MQCONNX(String,MQConnectOptions,Phconn,out int,out int) rc=OK
000002B8 14:45:52.636100   16832.1     IBM.WMQ.MQQueueManager#01475D71 throwing MQException: cc=2 rc=2059
000002B9 14:45:52.636100   16832.1     New MQException CompCode: 2 Reason: 2059
000002BA 14:45:52.662095   16832.1    --}! MQQueueManager.Connect() rc=(Unknown(2059))

Server side Windows Event Log:

2/6/2020 16:00:18 - Process(4472.130285) User(MUSR_MQADMIN) Program(amqrmppa.exe) Host(MQ-TEIRESIAS-T) Installation(MQTest) VRMF(8.0.0.4) QMgr(MQ.EXTSERVICES)

Error on receive from host 10.0.8.46.

An error occurred receiving data from 10.0.8.46 over TCP/IP. This may be due to a communications failure.

The return code from the TCP/IP recv() call was 10054 (X'2746'). Record these values and tell the systems administrator.

This is working code with amqmdnet.dll (9.0.0.0)

We appreciate any help or how can contact IBM Support for this

The issue has been resolved in APAR IT31572. Fix provided by IBM, tested and verified OK. Awaiting feedback on when to be published to NuGet/IBM. APAR IT31572 is not yet public.

https://www.ibm.com/support/pages/apar/IT31572