I-756x USB-to-Series device (COM4) Driver

The I-756x USB-to-Series device (COM4) driver enables Windows to communicate with the adapter through a serial COM port, allowing compatible software to exchange data with connected equipment. This Prolific driver is intended for users setting up the device for the first time, restoring a missing COM port, or troubleshooting communication problems after a system change.

Key Features

• Provides USB-to-serial communication support so applications can access equipment connected through the adapter.
• Allows Windows to recognize the device and expose its assigned serial port in Device Manager. The COM4 designation may change if Windows assigns a different port number.
• Supports use on Windows 10, 8.1, 7, Vista, and XP when the package matches the device hardware and operating system architecture.
• Enables compatible applications to use serial connection settings, such as baud rate and flow control, appropriate for the connected equipment.

How to Install I-756x USB-to-Series device (COM4) Driver

1. Check your Windows version and whether it uses a 32-bit or 64-bit architecture. In Device Manager, check the adapter’s hardware IDs if you need to confirm which package matches your device.
2. Choose the I-756x USB-to-Series device (COM4) driver download for Windows that matches your system. Before selecting a free download, verify its source and compatibility details rather than assuming every Prolific package supports this adapter.
3. Extract the downloaded archive if necessary. Run the included installer and follow its prompts to install the driver. If no installer is provided, open Device Manager, select the adapter, choose Update driver, and browse to the extracted driver folder.
4. Restart Windows if prompted, then connect or reconnect the adapter. Open Device Manager and look under Ports (COM & LPT) to confirm that it appears without a warning icon.
5. Select the assigned COM port in your serial application and match its communication settings to the connected equipment. For Windows 10/11 systems, check compatibility carefully: Windows 10 is listed as supported, but Windows 11 support is not confirmed here.

Keep the driver updated when a compatible release addresses a connection issue or operating system change. Check that the latest version supports your specific hardware before you update, and retain a working installer in case you need to restore the previous setup.