Like I said in the other thread, the Simulate mouse down case calls a windows function called "PostMessage". It posts a mouse down message to a specific window. That means you have to give it the window name. That's what the string control is for. Like I said, for more than this, you will have to look into the mouse functions in MSDN and for DLL tutorials here.
The question should be "do you really need a mouse click"? Many things can be solved without simulating a click.
To learn more about LV, I suggest you start by reading the LabVIEW user manual. Also, try searching this site and google for LabVIEW tutorials.
Here is one you can start with and
here is another. You can also contact your local NI office and join one of their courses.
In addition, I suggest you read
the LabVIEW style guide.
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