However, a major frustration arises when plugging this adapter into a PC. The operating system may fail to recognize it, label it as an “Unknown USB Device,” or throw a dreaded Code 10 or Code 31 error . The culprit? Windows 10’s strict driver signature enforcement and the proliferation of counterfeit Prolific chipsets.
This driver is not digitally signed for Windows 10. You must permanently or temporarily disable driver signature enforcement OR use a modified .inf file.
Meta Description: Struggling to connect your U232 P9 USB to Serial adapter on Windows 10? This guide covers driver download links, step-by-step installation, error fixes (Code 10, Code 31), and legacy COM port settings. Introduction: The Enduring Need for the U232 P9 In an era of USB-C and wireless connectivity, the humble U232 P9 (often labeled as USB 2.0 to Serial RS232 DB9 ) remains an essential tool for network engineers, industrial automation technicians, and hobbyists. This adapter bridges the gap between modern laptops without legacy COM ports and older equipment like Cisco routers, CNC machines, GPS receivers, and POS systems.
