Cable Integrity: If you see "Device Not Recognized" before even installing drivers, the internal wiring of the U232 P9 may be frayed. Share public link
Microsoft enforced stricter driver signing. Prolific used this opportunity to block counterfeit chips. Your Windows 7 driver (v3.x) is not compatible with Windows 10’s kernel.
To help narrow down any remaining installation roadblocks, please tell me:
Do not rely on generic Windows updates. You must download the specific driver package designed for the MCT or Prolific chipset used in the U232 P9.
Uncheck "Show compatible hardware" if needed, look for an older driver version (2015 or earlier), select it, and click . Disabling Driver Signature Enforcement u232 p9 driver windows 10
Navigate to the tab and click Device Installation Settings .
: If the device shows a "Code 10" error in Device Manager, you may need to manually select the driver using the "Let me pick from a list" method . Useful Features Beyond simple connectivity, the
Ensure the , Data bits , Parity , and Stop bits match the exact specifications required by your connected serial machine. Final Thoughts: When to Replace the Hardware
If your cable shows VID 0711 , search specifically for the and repeat the manual installation steps detailed in Method 1. Troubleshooting Common Post-Installation Issues The Adapter Disappears or Changes COM Ports Cable Integrity: If you see "Device Not Recognized"
Check the COM Port number: Some older software cannot communicate with COM ports higher than COM4. You can change this in Device Manager > Properties > Port Settings > Advanced.
Select .
As we have seen, the key is understanding the "why" behind the errors. The Code 10 error is rarely a sign of a broken device, but a symptom of a driver conflict. By employing the strategies outlined in this guide—from utilizing the official driver for newer chips to installing the legacy 3.3.2.102 driver and disabling signature enforcement as a last resort—you can successfully revive your adapter and restore reliable serial communication on your Windows 10 system. With patience and the right method, your U232-P9 can continue to serve its purpose for many years to come.
Configure to "None" or "Hardware" depending on your software specifications. Your Windows 7 driver (v3
Right-click your problematic U232 P9 / Prolific device and select .
I can give you the exact driver version link or registry configuration file you need. Share public link
your computer to ensure Windows fully recognizes the new COM port.