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Modbus read input registers on another PC returns zero values

Sorry if I'm not entering this into the Forum correctly as this is my first posting.

I have a program running ok on my PC with LV2016, but copying the program to another PC (running student edition 2016) (as well as another PC running 2012 executable which does the same) when reading 8 input registers returns data only for the 1st register while the others appear not to have been read/returned as they are zero and shaded out. I'm using the Modbus "WR" VI which sends the Modbus request then reads back the returned data. This VI and its two levels of sub-VIs show no errors (all have green checks) but also appears not to realize that not all 8 register values are returned. I reviewed the list of items in Software in NI MAX showing the VISA and related drivers appear the same. Both PCs have NI Serial and NI VISA installed. Bringing up Windows Device Manager for the serial ports also comes up the same. Any suggestions for what is going wrong on the other PCs?

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It turns out that although the other PC had downloaded all the latest from National including separate downloads of DAQmx, NI Serial and NI Modbus, there was some difference in my 5.21GB National Instruments folder and the other PC. After copying my folder onto the other PC, the program ran fine. 

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