It looks like you have already determined that the datatable object will be the best way to do this. When you are creating the object, you must enter the absolute path to your spreadsheet file. Then, you have to create some type of connection (i.e. a pushbutton or timer) that will send a true to the import data member of the datatable object. After these two things have been done, you will be able to access the data using the A3 - K133 data members.
Regards,
Michael Shasteen
Applications Engineering
National Instruments
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