the serial monitor is part of the same arduino software, just a pop in window to display the results.
both arduino and labview using the same port.
but i guess i figured out the problem as i got a message usbser.sys
USB serial driver (Usbser.sys)
i looked in my computer and i didn't find this driver, so i need to install it.
the Solution is updating the drivers and install all the missing files.
now is working properly.
Then you should mark Wiebe's message #7 as the solution to your problem. He was the one who suggested out of date drivers and to update them.