You can also replace the existing device driver with libusb-win32 device driver if desired. This is the preferred way to use libusb-win32. When you use the Inf-Wizard GUI to replace a device with inbox driver (like HID or USB Mass Storage Device), you may need to repeat the process if you plug in a same device but with different serial number. The package provides the installation files for FTDI USB Serial Port Driver version 2.12.16.0. If the driver is already installed on your system, updating (overwrite-installing) may fix various.
Windows versions
- Windows 10 for desktop editions (Home, Pro, Enterprise, and Education)
- Windows 10 Mobile
Common points of discussion for OEMs who want to build Windows systems with USB Type-C connectors.
USB Type-C connector features
Symmetric and reversible design
- The connector is symmetric. The cable has a USB Type-C connector on each end allowing the host and function device to use USB Type-C connectors. Here is an image that compares the connectors:
- The connector is designed to be reversible. Traditional connectors had to be connected the 'right-side-up'. With the reversible design, the connector can be flipped.
Supports all USB device speeds
The connector can support USB devices that are low-speed, full-speed, high-speed, SuperSpeed (including SS+).
Alternate modes
The connector can support alternate modes. The alternate mode feature allows non-USB protocols to run over the USB cable, while simultaneously preserving USB 2.0 and charging functionality. Currently, the most popular alternate modes are DisplayPort/DockPort and MHL.
DisplayPort / DockPort
This alternate mode allows the user to project audio/video to external DisplayPort displays over a USB connector.
MHL
The MHL alternate mode is allows the user to project video/audio to external displays that support MHL.
Billboard error messages
If a user connects a USB Type-C alternate mode device or adapter that is not supported by the attached PC or phone, the device or adapter can expose a Billboard device that contains information about the error condition to help the user troubleshoot issues.
Increased power limits
A system with USB Type-C connectors has higher power limits, it can support up to 5V, 3A, 15W.
In addition, the connector can optionally support the power delivery feature as defined by the USB Power Delivery OEM . If the connector supports power delivery, a USB Type-C system can be a power source provider or a consumer and support up to 100W.
Supports USB dual roles
Peripheral devices can connect to a mobile system with USB Type-C connectors, changing the traditional role of a mobile system from function to host. When the same system is connected to a PC, the system resumes the role of a function and PC becomes the host.
Operating system input into which alternate mode needs to be negotiated, such as DP 2-lane vs. DP 4-lane
No. The operating system (or any Microsoft-provided software component) plays no part in selecting an alternate mode. The decision is made by the driver for the connector, specifically the USB connector manager (UCM) client driver. The driver does so by communicating with the connector's firmware by using hardware interfaces.
Pre-OS charging with Type-C and PD
Enabling pre-OS charging is owned by the OEM. You can choose to not implement USB Power Delivery, and charge at USB Type-C power levels until you boot into the operating system.
Charging the phone when it is a USB host to enable docking scenarios like Continuum
Drew Port Devices Drivers
Here are a few things to consider:
You must to implement USB Power Delivery, so that power and data roles can be swapped independently.
Your dock’s upstream port should be implemented as a Charging UFP, defined in the USB Type-C specification. For details, see section 4.8.4, version 1.1.
Your dock should request a DR_Swap if it resolved to a DFP, or a PR_Swap if it resolved to a UFP.
The initial DFP is the power source, so you must change the data role. The initial UFP is the power sink, so you must change the power role. You can perform those operations in your implementation of these callback functions:
Windows 10 Mobile support of USB billboard devices
Yes, if you connect the phone to a device that supports a USB Billboard, as per the USB Device Class Definition for Billboard Devices specification, the user is notified. Your USB connector manager (UCM) client driver is not required to handle the notification. If your system does not recognize the alternate mode, do not enter the mode.
Support for USB Type-C on earlier versions of Windows
USB Type-C is not supported on versions of Windows prior to Windows 10.
UCSI support on earlier versions of Windows
UCSI is not supported on versions of Windows prior to Windows 10.
How to test an implementation of UCSI
To test your implementation, follow the guidelines given in USB Type-C manual interoperability test procedures. We recommend running USB tests in Windows Hardware Lab Kit (HLK) for Windows 10. These tests are listed in Windows Hardware Certification Kit Tests for USB.
Conditions and UI for the different errors
Windows 10 can show a set of USB Type-C error messages to help educate users about the limitations with different combinations of USB Type-C hardware and software. For example, the user might get 'Device is charging slowly' message if the charger connected to the USB Type-C connector is not powerful enough, not compatible with the system, or is connected to a non-charging port. For more information, see Troubleshoot messages for a USB Type-C Windows system.
Connecting a non-PD port to a PD provider and a PD consumer to a system that is not a PD provider
The non-PD port attempts to charge the system by using USB Type-C current levels. For more information, see USB 3.1 and USB Type-C specifications.
Connecting Thunderbolt, SuperMHL, or PCI express to a PC that does not support those capabilities
The alternate mode feature allows non-USB protocols (such as Thunderbolt, SuperMHL) to run over the USB cable, while simultaneously preserving USB 2.0 and charging functionality. If a user connects a USB Type-C alternate mode device or adapter that is not supported by the attached PC or phone running Windows 10, an error condition is detected and a message is shown to the user.
- If the device or adapter exposes a Billboard device, the user sees information about the error condition to help the troubleshoot issues. Windows 10 provides an in-box driver for a Billboard device and notifies the user that an error has occurred.
- The user might see an error notification, 'Try improving the USB connection'. For more information, see Fix USB-C Problems.
For the best results, make sure that the alternate mode device or adapter’s requirements are met by PC or phone or cable.
Support and limitations for MTP over USB Type-C in Windows
Windows 10 for desktop editions supports MTP in the initiator role; Windows 10 Mobile supports MTP in the responder role.
How downstream devices and hubs connect and communicate with USB Connector Manager (UCM)
UCM is its own device stack (see Architecture: USB Type-C design for a Windows system). Windows 10 support for USB Type-C includes the required plumbing to make sure that the different class drivers know how to communicate with the different USB Type-C connectors. In order to get Windows 10 support for USB Type-C, you must plug into the UCM device stack.
USB Type-C MUTT requirements for HLK tests
The Windows HLK for Windows 10 contains tests for USB host and function controllers. To test your system, use a USB C-A adapter. These tests are listed in Windows Hardware Certification Kit Tests for USB.
Microsoft support for P2P data transfer between the same Windows 10 SKU
This is not a valid connection.
- You cannot connect two PCs running Windows 10 for desktop editions.
- You cannot connect two mobile devices running Windows 10 Mobile.
If the user attempts to make such a connection, Windows shows an error message. For more information, see Error messages for a USB Type-C Windows system.
The only valid connection is between a Windows Mobile device and Windows desktop device.
UCM class extension (UcmCx) communication with PMIC or battery driver to get/set charging status
On software-assisted charging platforms, UcmCx communicates with PMIC and the battery subsystem. The client driver may determine the charging levels by communicating with the hardware through hardware interfaces. On hardware-assisted platforms, the embedded controller is responsible for charging. UcmCx takes no part in the process.
HLK support for USB Type-C
In Windows HLK for Windows 10, there are no USB Type-C specific tests. We recommend running USB tests in Windows HLK for Windows 10. These tests are listed in Windows Hardware Certification Kit Tests for USB.
UCSI
USB Type-C Connector System Software Interface (UCSI) Specification describes the capabilities of the USB Type-C Connector System software Interface (UCSI), and explains the registers and data structures, for hardware component designers, system builders, and device driver developers.
Microsoft provides an in-box driver with Windows, UcmUcsi.sys, that implements the features defined by the specification. This driver is intended for systems with embedded controllers.
Test a UCSI implementation running on Windows 10
We recommend running USB tests in Windows HLK for Windows 10. These tests are listed in Windows Hardware Certification Kit Tests for USB.
Test a UCMCx client driver on Windows 10
We recommend running USB tests in Windows HLK for Windows 10. These tests are listed in Windows Hardware Certification Kit Tests for USB.
VBus/VConn control and role switch operations handled by the UCM class extension
The UCM class extension might get requests from the operating system to change data or power direction of the connector. When it gets those requests, it invokes client driver's implementation of EVT_UCM_CONNECTOR_SET_DATA_ROLE and EVT_UCM_CONNECTOR_SET_POWER_ROLE callback functions (if the connector implements PD). In the implementation, the client driver is expected control the VBUS and VCONN pins. For more information about those callback functions, see Write a USB Type-C connector driver.
Dec 21, 2020 • Filed to: USB Recovery • Proven solutions
Have you ever had difficulty connecting your devices to your computer using a Prolific USB to Serial adapter? If yes you are lucky to find this page, it will give you all the information need to fix an unresponsive Serial driver adapter. You may have noticed a yellow exclamation mark hovering over or beside the USB to Serial Driver when searching your Device Manager and if you have we can all agree that it signifies a prevailing problem.
Overview of the Error
If you are not able to connect your device to your PC using a USB to Serial adapter it may be that
- The USB driver is outdated
- The USB Driver is missing
- Or even a corrupted driver
Drew Port Devices Driver Updater
While you can't be so sure what the exact problem is there are solutions you can adopt to fix the issue once and for all. Read on to find quick fixes to resolve the problem.
1# Fix Prolific USB to Serial Driver not Working
Solution: Roll your Prolific USB to Serial Driver back to an older version
Updating your drivers often work wonders for your system because it makes sure that it runs on the latest features that guarantee maximum functionality. Unfortunately updating your drivers can cause this kind of error especially if your latest update does not work too well with your hardware. Once you upgrade your PC to the latest Windows version your Prolific USB to Serial Driver also updates to the latest driver software and if the driver is not compatible with your Hardware issues may arise. To correct the error, you will have to download the driver again by following these steps.
- Right-click on your PC Start button and open Device Manager
- Double click LPT and COM ports then locate the Prolific USB to Serial Driver and right-click it so you can select Update Driver
- For driver software click My computer
- From My computer select 'Let me pick from a list of drivers available'
- Choose an older version from the list then click Next
- The driver you selected will be installed automatically
- Once it has been downloaded reconnect the driver to see if it works.
2# Fix Prolific USB to Serial Driver 'Coder 10'
Drew Port Devices Driver
Driver issues reveal themselves in so many ways or through messages such as
- This device will not start (Code 10)
- There is no driver installed in this device
- The driver was not successfully installed
A code 10 error may arise because the chip you are using is not an original one. If you are using a fake, the manufacturer has a way of disabling it due to copy write infringement and the copy write takes effect once you download a recent update. To protect your PC from getting this code, you will have to make sure that your Windows 10 never updates a driver without approval. Updates come in the form of 64 bit and 32-bit drivers. Below we will show you how to work your way around the problem.

Window 64 bit Fix
To fix Windows 64 bit OS including Prolific USB to Serial Adapter, follow through these steps.
- Download 'PL2303_64bit_Installer.exe and Save
- Remove every USB to Serial adapter from your PC and double click the 'PL2303_64bit_installer.exe
- Follow the prompt by plugging in one USB to Serial adapter the click on Continue
- Reboot your PC to get Windows up and running

Drew Port Devices Driver Ed
If you have followed these process through and you still see the same error go to your device manager
- Open the control panel and navigate to Device Manager
- From your control panel navigate to the System category and click the Hardware tab
- Scroll to the LPT/COM port and double click Prolific USB to Serial Comm Port
- Click Drivers in the Properties section
- The Driver you choose should read '3.3.2.102 with an appropriate date attached
- If the date is wrong then it means the wrong driver was installed
- Unplug the Serial adapter and run the steps again to install the correct driver
Window 32-bit
For Windows 32-bit OS systems follow these steps
- You will have to download the 'PL-2303_Driver_Installer.exe and save from Microsoft download link
- Run the program and eradicate the driver if you can
- Run the installer once more to install a correct driver
To Troubleshoot for error if your device still does not work
- Go to Control panel, enter System to access your Device Manager
- Scroll down to the LPT/ COM port then double click Prolific USB to Serial Comm Port
- Click Driver in the Windows Properties section
- The driver must be numbered as '2.0.2.8' and dates accordingly
If the driver was not installed, remove the Serial adapter then run 'PL2303_Driver_Installer.exe' again. Follow directions in Device Manager to download the correct driver
Drew Port Devices Driver Device
The three solutions listed in this article have proven to be quite helpful in fixing a Prolific USB to Serial driver not working on Windows 10. They may appear confusing at first but if you follow each step in detail you can resolve the issue.
Video Tutorial on How to Fix USB Device Not Recognized
USB Solution
- Recover USB Drive
- Format USB Drive
- Fix/Repair USB Drive
- Know USB Drive
