Dear Victor Rondón,

Thank you for reaching out regarding the issue with your USB serial CH340 chipset not functioning properly after installing the Windows 10 KB5046613 and KB5046542 updates.

Let’s work on troubleshooting and resolving this problem.

1. Check the Current Driver Version

• Connect the USB Serial Adapter to your computer.
• Open Device Manager (Windows + X > Device Manager).
• Expand the Ports (COM & LPT) section.
• Right-click the CH340 device, select Properties, and navigate to the Driver tab.
• Check the driver version and date.
• If the driver is newer than the 2019 version, proceed to roll back or reinstall the compatible version.

2. Roll Back to the 2019 Driver Version

• In Device Manager, right-click the CH340 device and select Properties.
• Go to the Driver tab and click Roll Back Driver (if available).
• Restart your computer and test the device again.
• If the rollback option is unavailable, proceed with the manual installation of the 2019 driver.

3. Manually Reinstall the 2019 WCH Driver

• Download the compatible driver from wch.cn’s website or your device manufacturer’s site.
• Disconnect the USB serial adapter.
• In Device Manager, uninstall the current driver:
  • Right-click the CH340 device.
  • Select Uninstall Device and check Delete the driver software for this device (if prompted).
• Restart your computer.
• Install the 2019 driver manually by running the installer or using the Update Driver option in Device Manager.
• Reconnect the USB adapter and test functionality.

4. Block Windows from Updating the Driver Automatically

• Press Windows + R, type gpedit.msc, and press Enter.
• Navigate to Computer Configuration > Administrative Templates > System > Device Installation > Device Installation Restrictions.
• Enable the policy "Prevent installation of devices that match any of these device IDs".
• Add your device’s hardware ID to the list:
  • Right-click the CH340 device in Device Manager.
  • Go to Properties > Details and select Hardware Ids from the dropdown.
  • Copy and paste the hardware ID into the group policy configuration.
• Apply the policy and restart your computer.

5. Disable Automatic Driver Updates

1. Press Win + R, type sysdm.cpl, and press Enter.
2. Go to the Hardware tab and click Device Installation Settings.
3. Choose No (your device might not work as expected) and save the changes.

6. Install Driver in Compatibility Mode:

1. Download the stable driver from wch.cn here.
2. Right-click on the driver installer file and select Properties.
3. Go to the Compatibility tab, check Run this program in compatibility mode for and choose Windows 7 or Windows 8 from the list.
4. Click Apply and run the installer.

If the issue persists, please reach out to the manufacturer of the USB Serial Adapter or visit their support forums for any known issues or updated drivers that may not be listed publicly.

Best Regards,

Martin | Microsoft Community Support Specialist