In some cases, Windows fails to install the compatible drivers, and you face issues like PL2303 phased-out error. These drivers help Windows read the device and communicate with it. When a device is connected to the computer, Windows automatically installs corresponding drivers. Are you facing difficulty with your Prolific USB serial adapter and encountering the PL2303 phased-out error/pl2303hxa phased-out error? Luckily, you are reading the right post that will help fix the issue and will make the yellow exclamation mark disappear.Ī USB-to Serial adapter cable connects your PC to the devices with serial ports, like PLC (Programmable Logic Controller).