OPC DCOM write error

Hi, everyone
I am facing the following problem when trying to write to the MFX’s MCO1OPC server.
I am getting following error in log file.
What may be the cause of such issue?

INFO   | jvm 1    | 2017/08/30 16:17:58 | ERROR [COMSubscription               ] [16:17:58,285]: Error executing write to OPC-COM items.
INFO   | jvm 1    | 2017/08/30 16:17:58 | java.lang.NullPointerException
INFO   | jvm 1    | 2017/08/30 16:17:58 | 	at com.jniwrapper.PrimitiveArray.<init>(SourceFile:88)
INFO   | jvm 1    | 2017/08/30 16:17:58 | 	at com.inductiveautomation.opccom.wrapper.subscriptions.COMSubscription$AsyncWriteJob.oleloop_startWrite(COMSubscription.java:1484)
INFO   | jvm 1    | 2017/08/30 16:17:58 | 	at com.inductiveautomation.opccom.wrapper.subscriptions.COMSubscription$WriteJob.internalRun(COMSubscription.java:1338)
INFO   | jvm 1    | 2017/08/30 16:17:58 | 	at com.inductiveautomation.opccom.wrapper.OleJob.run(OleJob.java:47)
INFO   | jvm 1    | 2017/08/30 16:17:58 | 	at com.jniwrapper.win32.MessageLoopThread$ThreadSynchronizedAction.run(MessageLoopThread.java:620)
INFO   | jvm 1    | 2017/08/30 16:17:58 | 	at com.jniwrapper.win32.MessageLoopThread$LoopThread.run(MessageLoopThread.java:562)
INFO   | jvm 1    | 2017/08/30 16:17:58 | ERROR [Provider[TAS_D]               ] [16:17:58,287]: [[TAS_D]LOADING_SEQ/Loading_Seq_BC_5/Transaction_Qty] Error writing to OPC address [[MFX4 system]GANTRY4_5.CUT.CANBus.MeterModule_G5.ODMnf.2425-ProcessControl1.D-TransactionQuantity]. Result code: [INTERNAL_ERROR] null
INFO   | jvm 1    | 2017/08/30 16:17:58 | ERROR [Provider[TAS_D]               ] [16:17:58,287]: [[TAS_D]LOADING_SEQ/Loading_Seq_BC_5/Command] Error writing to OPC address [[MFX4 system]GANTRY4_5.CUT.CANBus.MeterModule_G5.ODMnf.2425-ProcessControl1.B-Command]. Result code: [INTERNAL_ERROR] null

what will be the reason for:

java.lang.NullPointerException
and
Result code: [INTERNAL_ERROR] null