Issue: Troubles establishing communication between HD600 Sound Level Meter and your PC.
Most likely cause - USB Driver is not installed.
Tips to resolve:
First, go into the Windows Device Manager and see which COM PORT it has been assigned to under PORTS. It will show up as CP210X. Next, make sure you match this port number in the HD600 Software. Once this is done, Press the “Setup” button on the HD600 itself and this will start the communication. If you see a device listed with either a yellow question mark or exclamation point then right click and do an Update Driver. Instead of searching automatically click Browse and then when you get to where you can type the path in, delete whatever it points you to and manually type in Your CD ROM Drive Letter (Example: D:\) and then click next. It should now find and install it.