If SpecView is displaying ‘XXX’ or ‘N/R’ for all values, then please open the SpecView help file from the Help menu, and search the help file ‘Troubleshooting Instrument Communications’.
In that section of the help is a lot of information about how to go about looking for the cause.
If you have recently moved SpecView from one computer to another, one reason could be that the communications port (COM) are different on the new computer compared to the old one. In this case, you might need to use the ‘Swap COM ports’ facility from the Setup Menu, see here for more details.
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