We use a Java program to send a PUT request to the MQ Server. Recently, we have seen intermittent errors. Sometimes it works without any problem, however, the error comes without any apparent reason.

I appreciate your help in troubleshooting this error.

From the client side, we see this error:

com.ibm.mq.MQException: MQJE001: Completion Code '2', Reason '2063'.
at com.ibm.mq.MQManagedConnectionJ11.<init>(MQManagedConnectionJ11.java:251)
at com.ibm.mq.MQClientManagedConnectionFactoryJ11._createManagedConnection(MQClientManagedConnectionFactoryJ11.java:449)
at com.ibm.mq.MQClientManagedConnectionFactoryJ11.createManagedConnection(MQClientManagedConnectionFactoryJ11.java:486)
at com.ibm.mq.StoredManagedConnection.<init>(StoredManagedConnection.java:97)
at com.ibm.mq.MQSimpleConnectionManager.allocateConnection(MQSimpleConnectionManager.java:194)
at com.ibm.mq.MQQueueManagerFactory.obtainBaseMQQueueManager(MQQueueManagerFactory.java:870)
at com.ibm.mq.MQQueueManagerFactory.procure(MQQueueManagerFactory.java:818)
at com.ibm.mq.MQQueueManagerFactory.constructQueueManager(MQQueueManagerFactory.java:760)
at com.ibm.mq.MQQueueManagerFactory.createQueueManager(MQQueueManagerFactory.java:200)
at com.ibm.mq.MQQueueManager.<init>(MQQueueManager.java:1004)
at MQUtility.main(MQUtility.java:333)

On MQ Server Error Log, we see the following errors:

----- amqzfubn.c : 3986 -------------------------------------------------------
4/26/2024 01:03:00 - Process(6200.26) User(SYSTEM) Program(amqrmppa.exe)
Host(HOTS-NAME) Installation(Installation1)
VRMF(9.0.3.0) QMgr(Test)
Time(2024-04-26T06:03:00.217Z)

AMQ9557: Queue Manager User ID initialization failed for 'user-name'.

EXPLANATION:
The call to initialize the User ID 'user-name' failed with CompCode 2 and Reason
2063. If an MQCSP block was users, the User ID in the MQCSP block was ''.
ACTION:
Correct the error and try again.
----- cmqxrsrv.c : 2350 -------------------------------------------------------
4/26/2024 01:03:02 - Process(4604.33) User(SYSTEM) Program(amqzlaa0.exe)
Host(HOST-NAME) Installation(Installation1)
VRMF(9.0.3.0) QMgr(Test)
Time(2024-04-26T06:03:02.387Z)

AMQ7227: IBM MQ encountered the following network error: The RPC server is
unavailable.

EXPLANATION:
MQ failed to successfully complete a network operation due to the specified
error. If the error is encountered on systems that are part of a Windows 2000
domain it can indicate incorrect DNS or WINS configuration.
ACTION:
Ensure that your network is functioning correctly. On the Windows platform
check DNS and/or WINS settings to ensure that domain controllers, used for
authentication or authorisation functions, are accessible.
----- amqzfubn.c : 3986 -------------------------------------------------------
4/26/2024 01:03:02 - Process(6200.27) User(SYSTEM) Program(amqrmppa.exe)
Host(HOST-NAME) Installation(Installation1)
VRMF(9.0.3.0) QMgr(Test)
Time(2024-04-26T06:03:02.387Z)

AMQ9557: Queue Manager User ID initialization failed for 'user-name'.

EXPLANATION:
The call to initialize the User ID 'user-name' failed with CompCode 2 and Reason
2063. If an MQCSP block was users, the User ID in the MQCSP block was ''.
ACTION:
Correct the error and try again.
----- cmqxrsrv.c : 2350 -------------------------------------------------------