--- End of inner exception stack trace ---
at OpcLabs.EasyOpc.DataAccess.EasyDAClient.CheckSuccess(OperationResult operationResult)
at OpcLabs.EasyOpc.DataAccess.EasyDAClient.ReadItem(ServerDescriptor serverDescriptor, DAItemDescriptor itemDescriptor, DAReadParameters readParameters)
at OpcLabs.EasyOpc.DataAccess.EasyDAClient.ReadItem(ServerDescriptor serverDescriptor, DAItemDescriptor itemDescriptor)
at OpcLabs.EasyOpc.DataAccess.EasyDAClient.ReadItem(String machineName, String serverClass, String itemId, VarType dataType)
at OpcLabs.EasyOpc.DataAccess.EasyDAClient.ReadItem(String machineName, String serverClass, String itemId)
at SPGPrints.Communication.OpcCommunicationModule.WriteValue[T](String deviceIdentifier, String itemIdentifier, T value)
2014-05-08 11:53:41.0866 WARN - QCSTATION1/QCStation/Communication - OPC WriteValue returns OpcException, e: OpcLabs.EasyOpc.OpcException: An OPC operation failure with error code -1073430509 (0xC004C013) occurred, originating from 'OpcLabs.EasyOpcRaw.DataAccess.RawEasyDAClient'. The inner exception contains details about the problem. ---> System.Runtime.InteropServices.COMException: Read not completed. This error indicates that it could not be verified that the requested read operation was completed during the timeout period. It is possible that the read operation will actually succeed or fail, but later. Increase the timeout period if you want to obtain positive or negative indication of the operation outcome. Other reason for this error may be that under heavy loads, topic request or response queue is overflowing. Check the event log for queue overflow errors (if event logging is supported by the product and enabled).
--- End of inner exception stack trace ---
The reason I am asking these questions is because when the DCOM is configured in certain way, the account under the OPC server runs may depend on who is logged on.