ISSUE: When trying to write to a USB device, there is a windows permissions popup (infinite cycle) for admin rights and still get an access denied.
It turns out that Antivirus (white list-er) is the culprit. In my case, Carbon Black. Even with the AV disabled, it was still blocking the USB. This is because CB uses the windows registry to block USB devices, and stopping the service will not help. You MUST go into the AV and permit the device, or hack the registy from an admin to permit it.