Because of the vast number of different manufacturers and models of USB-to-Serial adapters it would be impossible for us to verify the functionality of each one.
Here is a list of specific models of adapter that are approved and recommended for use with the PXL-500 controller.
1. Tripp-Lite Keyspan Model USA-19HS: Keyspan driver version 3.7.0.5, Driver Date = 5/13/2010
2. Plugable Model PL2303-DB9, Prolific Chipset PL-2303 HXD: Prolific driver version 3.6.81.357, Driver Date = 9/4/2015
3. TrendNet Model TU-S9, Prolific Chipset PL-2303 HXD: Prolific driver version 3.6.81.357, Driver Date = 9/4/2015
4. QVS Model UR-2000M2, Prolific Chipset PL-2303 RA: Prolific driver version 3.6.81.357, Driver Date = 9/4/2015
5. Best Buy Insignia Model NS-PU99501, Prolific Chipset PL-2303 RA: Prolific driver version 3.4.62.293, Driver Date = 10/17/2013
6. I/O Gear Model GUC232A: ATEN / Prolific driver version 3.3.7.131, Driver Date = 10/15/2009
7. FTDI chipset generic adapter: FTDI driver version 2.8.30.0, Driver Date = 7/12/2013
It is also recommended to install the device driver that comes with the device. Otherwise, ensure the PC is connected to the internet when installing the device (so that Windows can also search the internet for the correct driver).