I'm not sure which LV or FieldPoint Version you have. I habe FP 4.1 with LV 7.1.1.
The help here is more precise. Meant is that you should open one iak-File only with one FP Open call. Then you should use the Refnum in your program.
The iak-File is created using MAX. A iak-File is the representation of your FieldPoint hardware. Since you have two TC-120 units you have these in your iak-File. They have two different modul adresses.
Look into the picture about how to organize your programm flow.
Waldemar
Using 7.1.1, 8.5.1, 8.6.1, 2009 on XP and RT
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