Public Property Source As String

public string Source { get; set; }

public:
property String^ Source {
	String^ get ();
	void set (String^ value);
}

For E Series DAQ devices, if you specify a channel name as source, the channel must be the first channel in the task. Also, the only terminal you can use for E Series devices is PFI0.

Refer to the NI-DAQmx Device Terminals Help to find terminal names for devices supported in NI-DAQmx.