The Modbus VIs can return the following error codes. Refer to the KnowledgeBase for more information about correcting errors in LabVIEW.

Code Description
−389122 The target device does not have any response. Possible reason: the target device is not present on the network. This error description is defined by the Modbus Organization.
−389121 The gateway is unable to allocate an internal communication path from the input port to the output port for processing the request. Possible reason: the gateway is either misconfigured or overloaded. This error description is defined by the Modbus Organization.
−389118 An extended file area failed to pass a consistency check. You can use the Modbus master to retry the connection, but the Modbus slave may require certain service. This error description is defined by the Modbus Organization.
−389116 The Modbus slave is busy. Use the Modbus master to retransmit data at a later time. This error description is defined by the Modbus Organization.
−389115 The Modbus slave is processing the request and may spend a long time processing this request. This error description is defined by the Modbus Organization.
−389114 An unrecoverable error occurred while the server was attempting to perform the requested action. This error description is defined by the Modbus Organization.
−389113 A value contained in the query data field is invalid for the Modbus slave. This error description is defined by the Modbus Organization.
−389112 The Modbus slave does not accept the data address contained in the query. This error description is defined by the Modbus Organization.
−389111 The Modbus slave does not accept the function code contained in the query. This error description is defined by the Modbus Organization.
−389107 The Modbus master does not use a serial protocol and cannot perform the action that you requested. Ensure that you use a serial Modbus master to perform this action.
−389106 The current Modbus slave cannot perform the operation you wanted to perform, because this slave is not a TCP Modbus slave.
−389105 The Modbus slave daemon, also known as background process, failed to launch. Contact National Instruments for technical support.
−389104 The object that you write exceeds 244 bytes in length.
−389103 The object that you specified does not exist in the Modbus slave. Ensure that you specify an object that exists in the Modbus slave. Contact National Instruments for technical support.
−389102 The data that the Modbus slave returned did not match the data that the Modbus master sent for the operation you want to perform. Contact National Instruments for technical support.
−389101 The returned Modbus Encapsulated Interface type was not 0x0E (14). This type is required for the operation you want to perform. Possible reasons: the Modbus slave does not have a device identification; the Modbus slave does not support read operations on its device identification.
−389100 The returned function code does not match the function code in the requested data. Contact National Instruments for technical support.
389298 The operation you want to perform is not implemented. Possible reasons: the descendant class does not implement one of the required member VIs in the ancestor Modbus class; the descendant class data is lost and LabVIEW executes a member VI in the ancestor Modbus class that does not provide an implementation. Contact National Instruments for technical support.
389299 You configured this serial request as a broadcast. The Modbus slave does not respond to broadcasts. Contact National Instruments for technical support.