USB to RS232 Serial COM port converter showing Error Code 10 in Windows Device Manager

Root Cause Diagnosis

Device Manager throws Error Code 10 (“This device cannot start”) on USB-to-RS232 adapters when the vendor driver fails to initialize the hardware interface due to a driver-chipset mismatch or a revoked digital signature. This most commonly occurs when Windows Update automatically installs modern driver versions (such as Prolific PL2303 v3.8+ or FTDI v2.12+) that actively block counterfeit or end-of-life (EOL) bridge ICs by returning an invalid hardware ID payload. As a result, the kernel serial driver (serenum.sys or usbser.sys) fails its device start routines during I/O Request Packet (IRP) allocation.

Quick Fix

Roll back the serial adapter driver to an archived legacy driver version (e.g., Prolific v3.3.2.102 or FTDI v2.08.24) and disable driver auto-updates via PowerShell:

# Run as Administrator to prevent Windows from overwriting the legacy driver
Set-ItemProperty -Path "HKLM:\SOFTWARE\Policies\Microsoft\Windows\DriverSearching" -Name "SearchOrderConfig" -Value 0

Then, open Device Manager, right-click the failing serial device, select Update driver > Browse my computer for drivers > Let me pick from a list of available drivers on my computer, and choose the older driver release.

Step-by-Step Resolution

1. Hardware Chipset & Vid/Pid Identification

1. Open Device Manager (devmgmt.msc).
2. Expand Ports (COM & LPT) or Other devices, right-click the problematic device with the yellow exclamation mark, and select Properties.
3. Navigate to the Details tab and change the property dropdown to Hardware Ids.
4. Read the Vendor ID (VID) and Product ID (PID):

• Prolific PL2303: VID_067B&PID_2303
• FTDI FT232R: VID_0403&PID_6001
• CH340 / CH341: VID_1A86&PID_7523
• Silicon Labs CP210x: VID_10C4&PID_EA60

2. Driver Purge and Legacy Driver Installation

1. Disconnect the USB-to-RS232 hardware from the host system.
2. Open PowerShell as Administrator and forcibly purge the problematic driver package from the Windows Driver Store:

# List published third-party drivers
pnputil /enum-drivers

# Identify the OEM file corresponding to the failing driver (e.g., oem12.inf) and force delete it
pnputil /delete-driver oem12.inf /uninstall /force

3. Download and install the verified legacy driver installer corresponding to your chipset (e.g., Prolific driver version 3.3.2.102 for legacy PL2303 HXA/X chips).
4. Re-insert the USB-to-RS232 adapter.

3. Assigning Fixed Driver & Device Instance Override

1. Open Device Manager, right-click the device, and choose Update driver.
2. Select Browse my computer for drivers, then click Let me pick from a list of available drivers on my computer.
3. Uncheck Show compatible hardware if necessary, locate the matching legacy driver version (look for dated releases prior to 2015 for PL2303 chips), and click Next.
4. Confirm the installation. Verify that the device status under Properties > General updates to “This device is working properly.”
5. Navigate to Port Settings > Advanced and assign a static COM Port number (e.g., COM3) between COM1 and COM8 to avoid high-index port binding conflicts.

Why This Fails for Some Users

• Windows 11 Memory Integrity (HVCI) Enforcement: On modern Windows 11 installations, Hypervisor-Protected Code Integrity (HVCI) blocks legacy drivers (such as pre-2012 Prolific or FTDI drivers) from loading because they lack modern WHQL signatures or contain vulnerable kernel code execution vectors. Resolving this requires either replacing the adapter hardware or disabling Memory Integrity under Windows Security > Device Security > Core Isolation, which reduces system security.
• FTDI “Brick” Countermeasure EEPROM Rewriting: Older FTDI driver releases actively erased or zeroed out the USB PID (changing PID_6001 to PID_0000) on non-authentic FTDI chips upon enumeration. If the PID has been overwritten to 0000, Windows will recognize the device only as an unknown USB bridge, and standard driver installation steps will fail until the EEPROM is reprogrammed using utility software (such as FT_PROG).
• Insufficient USB Bus Power / Line Drivers: High-grade RS232 signaling requires full $\pm 5\text{V}$ to $\pm 15\text{V}$ swings on TX/RX lines. Unpowered USB hubs or low-voltage host ports may fail to supply sufficient power to the charge-pump IC (such as the MAX232 transceiver) inside low-cost converters, triggering an internal controller timeout that manifests as an OS-level Code 10 initialization failure.
• Group Policy Driver Installation Blockades: On enterprise-managed machines, Active Directory Group Policy Objects (GPO) located at Computer Configuration > Administrative Templates > System > Device Installation > Device Installation Restrictions may explicitly block non-WHQL certified USB drivers or prevent end-users from changing driver properties, silently reverting manually assigned legacy drivers upon reboot.