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Windows 7 64-bit not loading USB mass storage driver

    Question

  • I have a rather strange problem with my Windows 7 Ultimate 64-bit.  Everything seems to work fine except for USB mass storage devices.  I have USB keyboard, mouse and even a USB audio (wireless headset) all working fine on the computer.  But any USB external drive, thumdrive or USB card reader with flash cards inserted into the USB port of my computer won't work.

    Windows keeps reporting that it is unable to find the driver.  When I go into the Device Manager console and choose to manually update the driver, then point it to the C:\Windows (with search for sub-directories enabled), it detects the USB Mass Storage driver but complains that it is unable to load it.  The exact message is this:  Windows found driver software for your device but encountered error while attempting to install it.  USB Mass Storage Device.  The system cannot find the file specified.

    This happens to ALL USB Mass storage device, and it doesn't matter which port I plug the device into.

    Here's the weird thing, I have VMware Workstation installed on this computer and if I power on a VM that runs Windows 7 32-bit as the Guest OS and connect the USB storage devices to the guest OS via VMware Workstation, the USB storage devices work!

    So it would appear that the USB ports are functioning properly but for some reasons, my Windows 64-bit is unable to load the driver.

    Any idea how to fix this besides a "nuke it from orbit" and format/reinstall Windows?

    Thanks.

    Wednesday, May 15, 2013 2:58 AM

Answers

  • Found the problem.  For some strange reasons, a few files in the C:\Windows\inf directory went missing, 2 of those was usbstor.inf and usbstor.PNF.  What I did was to copy the C:\Windows\inf directory from my properly functioning laptop to this problematic computer (skipping all existing files) and it resolved the problem.

    Weird though, I never deleted anything from the INF directory, not sure how those USB Mass Storage driver files went missing in the first place.

    Wednesday, May 15, 2013 4:44 AM

All replies

  • Found the problem.  For some strange reasons, a few files in the C:\Windows\inf directory went missing, 2 of those was usbstor.inf and usbstor.PNF.  What I did was to copy the C:\Windows\inf directory from my properly functioning laptop to this problematic computer (skipping all existing files) and it resolved the problem.

    Weird though, I never deleted anything from the INF directory, not sure how those USB Mass Storage driver files went missing in the first place.

    Wednesday, May 15, 2013 4:44 AM
  • Glad to hear you found the resolution.

    Niki Han
    TechNet Community Support

    Thursday, May 16, 2013 3:36 AM
  • I'm very excited to finally have a solution for this problem. Thank You Balaji for figuring this out. I've been struggling with this for a number of years, and had only one USB Hard Drive that worked. I too have VMware workstation, and had the missing files in "c:\windows\inf." I can say with certainty that I did not delete the files from that folder, but something is common in both of our situations. Maybe it has to do with VMware, and some of it's updates over the years. I'm also using nCompute to share out a networked desktop via the wire. 

    One more thing worthy of mention is this machine was an update from Windows Vista, and the USB hard drive that worked was configured back than. So although I could never add another HD, at least I had the one.

    Now with having copied over the files, I can plugin other USB enclosures with different drives and they too are working.

    Like you mentioned, it was always possible to use USB devices within my Virtual Machines, so it was clear that the USB ports were functional. I actually got the files from a clean Windows 7 VM, copying out the \windows\inf folder and doing a compare between the the real one and the virtual one. I found the two missing files you mentioned, along with 8 others. I went ahead and included them all in your fix.

    It worked, Amazing. Thanks again. :O)

    Sunday, October 13, 2013 2:28 PM
  • Thank you, thank you, thank you!!!!
    Friday, October 18, 2013 3:50 PM