External USB hard drive problem

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I have a problem which has recently arisen on my Windows 10 PC concerning its USB ports.  The problem is that when I plug in an external USB hard drive none of the USB ports recognize any read/write device thereafter including any USB memory sticks, these previously working prior to plugging in the external USB hard drive.  These still don’t work after the hard drive has been unplugged.  My wireless mouse and USB camera are not affected and still work as normal whether or not the USB hard rive is plugged in.  After disconnecting the USB hard drive and doing a warm reboot of my PC the USB ports will allow USB memory sticks to be read and written to.  However, it takes a long time to reboot before restarting with the rotating circle of dots appearing.

Should an external USB hard drive be plugged into any of the USB ports when trying to start or reboot my PC then it just hangs at and never gets past the rotating circle of dots.

Through my Local Group Policy Editor under Local Group Policy>Computer Configuration>Administrative Templates>System>Removable Storage Access I’ve checked that all ‘Removable Disks; Deny Access’ are in a ‘Not configured’ state.

Looking at Device Manager I find an entry ‘User-mode block device’ that I don’t recall seeing before; I’m wondering if this could be the culprit (and there seems to be no way of deleting it).

Can anyone suggest what the problem is or offer a solution?

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It sounds like you may have run into Windows’ longstanding USB device enumeration bug, first introduced in Vista.

What happens is that Windows keeps a ‘history list’ in the registry whereby every time you plug a USB device in then a record is created of date, time, device ID, manufacturer, serial no. (if available) and device capability… plus the USB port which is used.

Unfortunately these records are not removed when the device is unplugged… they just continue to proliferate until eventually the registry hits an enumeration limit and the devices – usually mass storage devices like external hard disks – become ‘unknown’ or you can hear the Windows ‘connect’ noise but the devices just don’t appear in File Explorer.

You can test for this easily (and fix it) by using Nir Sofer’s small, free, portable USBDeview utility.

1. Download and unzip USBDeview. Make sure you choose the correct ‘bitness’ for your system (which is most likely using a 64-bit version of Windows).

2. Remove any connected USB devices except for mouse, keyboard and/or camera.

3. Right-click on the UsbDeview.exe file and select the Run as administrator… option. (This is important as USBDeview needs elevated rights to remove entries from the USB history list in the registry.)

4. Click on the word Connected at the top of its column. (This isn’t strictly necessary but it sorts the list and makes it less likely that you’ll accidentally disconnect any USB keyboard/mouse/camera in use.)

5. Looking at the first column, click on the first device that shows with a grey roundel (a green roundel indicates a connected device), hold the SHIFT key down then click on the last device that shows with a grey roundel. You have now selected all USB devices that are currently *disconnected*.

6. Select Uninstall Selected Devices from the File menu then click on the Yes button in the prompt that appears. (What this does is delete the USB device enumeration records in the registry for the devices you selected, hopefully bringing the total back to below the enumeration limit.)

You will be left with a list showing any remaining USB devices that are connected.

7. Close USBDeview and restart your PC. (This will let Windows repopulate the USB and USBSTOR keys in the registry under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\ used to store enumation info.)

Note: Apple devices connected via USB (like iPhones, iPads and iPods) have multiple connection modes (at least 3 per device) and take a long time – several minutes each – to re-install themselves if USBDeview is used to uninstall them.

As a result I tend to exclude any records in USBDeview that show Apple, Inc. in the Vendor Name column… unless it’s an Apple device that’s not being recognised.

Please let us know if this fixes the issue for you.

Hope this helps…

7 users thanked author for this post.

wavy, NaNoNyMouse, WSTerobitTony, DriftyDonN, JohnW, Alex5723, windbg

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Rick,

many thanks for your response to my problem.  I tried your suggestions but unfortunately they didn’t work.  I also deleted the ‘User-mode block device’ entry in Device Manager and, as it was authored by Paragon, also removed the Paragon Hard Disk Manager™ 15 Suite which was installed on my system, all to no avail.

Has anyone got any further ideas?

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WSTerobitTony wrote:

I also deleted the ‘User-mode block device’ entry in Device Manager and, as it was authored by Paragon, also removed the Paragon Hard Disk Manager™ 15 Suite which was installed on my system

Just FYI, that’s the driver Paragon uses to communicate with external USB drives during shadow copy operations.

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WSTerobitTony wrote:

Should an external USB hard drive be plugged into any of the USB ports when trying to start or reboot my PC then it just hangs at and never gets past the rotating circle of dots.

Depending on your boot configuration, your computer may be attempting to boot to the external hard drive. Remove the external hard drive prior to booting your computer.

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