Qualcomm HS-USB Diagnostics 250D (COM4) Driver

The Qualcomm HS-USB Diagnostics 250D (COM4) driver helps Windows recognize the diagnostic USB interface on compatible Qualcomm-based devices and makes it available to supported service tools through a COM port. Listed under Qualcomm Atheros in the USB category, this driver is intended for technicians, developers, and users who need diagnostic communication rather than ordinary USB file transfers.

Key Features

• Diagnostic USB connectivity: Enables compatible diagnostic software to communicate with the device through its exposed diagnostic interface.
• Serial port access: Supports recognition as a Windows COM port. Although the device name includes COM4, Windows may assign a different port number.
• Legacy Windows support: Listed operating systems include Windows 10, 8.1, 7, Vista, and XP. Choose a package that explicitly supports your Windows edition and system architecture.
• Device recognition: Installing the correct package may resolve a missing-driver warning for this interface in Device Manager, provided the hardware ID matches.

How to Install Qualcomm HS-USB Diagnostics 250D (COM4) Driver

1. Check your system and device. Confirm your Windows version and whether it is 32-bit or 64-bit. In Device Manager, open the device’s Properties and check Details > Hardware Ids to help identify a matching package.
2. Choose a compatible package. Before starting a Qualcomm HS-USB Diagnostics 250D (COM4) driver download for Windows, review the supported hardware and operating systems. For Windows 10/11 searches, note that Windows 10 is listed here, but Windows 11 compatibility is not confirmed.
3. Download and extract the files. Use a trusted source, even when a package is offered as a free download. Prefer a signed driver, scan the downloaded files, and extract the archive if necessary.
4. Install the driver. Run the supplied installer, or open Device Manager, right-click the diagnostic interface, and select Update driver. Browse to the extracted driver folder and follow the prompts. Do not force installation if Windows reports a compatibility problem.
5. Verify the connection. Restart if prompted, reconnect the device in its supported diagnostic mode, and check Device Manager for warnings. Select the assigned COM port in your compatible diagnostic application.

Keep the driver updated when a verified release addresses a connection issue or adds relevant compatibility. Before you update, confirm that the latest version still supports your device and operating system; a newer package is not automatically the right match for older Windows installations.