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Be sure as well to never use hub. I have many issues with USB hub. If you want to get the list of USB device connected, you can use this VI. note that if your web cam do now have embedded serial number, the device path is reported according to the USB port connected. if you connect the same model of webcam at the same port, Windows will use the same friendly name. I use Spinnel USB cam 2M. they do have a embedded serial number programmed upon request... 50$ per unit. quite decent for this usb camera with a low distortion lenses. USB Scanner.vi

One difference between LabVIEW and .Net is the threading for ActiveX components. While ActiveX components can be multithreading safe, they seldom really are and specify the so called Apartement threading to be required. This means that the component is safe to be called from any user thread but that all methods of an object need to be called from the same thread that was used when creating the object. In .Net as long as you do not use multi-threading by means of creating Thread() objects or some derivated objects of Thread(), your code runs single threaded (in the main() thread of your application). LabVIEW threading is more complicated and automatic multi-threading. This means that you do not have much control over how LabVIEW distributes code over the multiple threads. And the only thread execution system where LabVIEW does guarantee that all the code is called in the same thread is the UI Execution system. This also means that apartment threaded ActiveX objects are always executed in the UI Execution system and have to compete with other UI actions in LabVIEW and anything else that may need to be called in a single threaded context. This might also play a role here. Aside from that, I'm not really sure how LabVIEW should know to not create a new connection object each time, but instead reuse an already created one. .Net seems to somehow do it but the API you are using is in fact a .Net wrapper around the actual COM ADO API.

Raspberry Pi + machine learning + machine vision, sign me up! G Systems is sponsoring this door prize, an AIY Vision Kit from Google.

There are some private properties you can use in LabVIEW 2012 SP1 and later that allow you to set the focus row of a Listbox or Multicolumn Listbox programmatically. Whenever you programmatically change the value, if you also programmatically change the focus row, it should behave in the manner you're looking for. I had heard the behavior was fixed natively to the controls in LabVIEW 2013, but it appears to still be an issue that we have to workaround programmatically. This VI (saved in LabVIEW 2012) contains the private properties you would need. Again, these properties were added in 2012 SP1, so they're not available in an earlier version. Oh, and it was a top woman, not a top man, who added these private properties for us. Focus Row Properties.vi