A PC that has the development environment has the LV runtime and the VISA runtime already there. Running an .exe on that computer will not have a problem. Creating the .exe file on that computer does not magically install the run-time components into the executable. So running the .exe on a PC that does not have those run-time engines, the executable will not run. If you have the LV runtime but not the VISA runtime on another PC, the executable will run, but the serial functions will fail since the VISA run-time is not present.
You need to install both the LV and the VISA run-times. Two separate packages. You can get them directly from the NI website. Or you can create an installer on the same development PC you used to create the executable. In the build options of the installer, you can request to include one or both run-time engines.
