Because "RN10D" is the model number of the USB receiver, searching for it directly on the driver page sometimes yields no results. Instead, look for the software that manages it:
This sometimes happens on older Windows versions. It’s usually harmless, but you can manually install the driver by pointing Device Manager to the pairing utility’s folder. a4tech rn10d driver free
"Come on, you brick," he whispered, jiggling the USB cord. Because "RN10D" is the model number of the