The JMicron PCIe MS Host Controller driver lets Windows communicate with the Jmicron controller used for a Memory Stick card reader. Installing the correct driver can help Windows recognize the reader and access supported memory cards when the controller appears as an unknown device or is not working properly.

Key Features

• Memory Stick reader support: Enables communication between Windows and the controller so compatible Memory Stick media can be detected and accessed.
• File transfer functionality: Supports reading and writing files on compatible cards, subject to the reader’s capabilities and any write-protection settings.
• Windows compatibility: Driver versions are available for Windows 10, 8.1, 7, Vista, and XP. Choose a package that matches your operating system and its 32-bit or 64-bit architecture.
• Device recognition: Provides the driver information Windows needs to identify and configure the controller in Device Manager.

How to Install

1. Confirm your hardware and Windows version. Open Device Manager and locate the JMicron PCIe MS Host Controller or the unidentified card-reader device. If the name is unclear, check its hardware IDs under Properties > Details and compare them with the driver package’s supported devices.

1. Choose the matching driver. Download a Jmicron driver package intended for your controller and Windows version. A package for Windows XP or Vista should not be assumed to work on Windows 7, 8.1, or 10 unless those systems are explicitly supported.

1. Prepare the download. Extract the files if the package is compressed. Close applications using the card reader, safely eject any inserted memory card, and review any installation instructions included with the driver.

1. Install the driver. Run the supplied installer and follow its prompts. If no installer is included, open Device Manager, right-click the controller, select Update Driver, and browse to the extracted driver folder. The wording of these options varies by Windows version.

1. Restart and test the reader. Restart if prompted, then insert a known-compatible Memory Stick card. Check that the controller has no warning icon in Device Manager and that the card is accessible in File Explorer or Windows Explorer.

Although this device may be listed under the 1394 category, it is a PCIe Memory Stick host controller—not an IEEE 1394/FireWire controller. Match the driver to the actual hardware rather than relying on the category label alone.

Common Issues and Fixes

• Install fails or rolls back: Run the JMicron installer as administrator and use a package matching your Windows version/architecture. If blocked by driver signing, verify the source first; otherwise update manually via Device Manager using the extracted INF.
• Device not detected: Confirm the PCIe card reader is enabled in BIOS/UEFI and seated correctly. Check Device Manager for an unknown PCI device, then reseat the Memory Stick/adapter and test known-good media.
• Version conflicts: Remove older JMicron MS Host Controller drivers before installing the new package, restart, and avoid mixing vendor and Windows Update drivers. If a Windows update replaces it, roll back to the vendor driver.