External HDD visible in "Devices and Printers" but not recognised in Windows Explorer - Windows 7 64 bit.

Question

I have two external storage HDD - a 320GB Buffalo Ministation (it has a Samsung drive inside) and my principal backup drive is a Western Digital 1TB drive. I bouhgt my new notebook four months ago (Acer Aspire 4740) and upgraded the RAM to 4GB. Over the past two days my notebook has ceased to recognise either of my external drives in the explorer although it does the drives are connected when one looks under "Devices and Printers".

I have taken the following steps:

1. checked the drivers are up to date
2. "In win7, go to device manager... uninstall the external hard drive. Unplug the usb cable. Plug it back in. VOILA.

I know... it seems simple... and it was... but it took a LONG time to figure out." this came from a form here (http://social.answers.microsoft.com/Forums/en-US/w7hardware/thread/630f7c23-3dff-4df3-8557-d7897e42549d?prof=required)

This has all been futile. Ironically my older notebook, which runs XP, gives me full access to both the drives.

Please can somebody offer me some advice on how to deal with this issue.

Answer 1

Hi AFRICANHUDSON,

a)   Have you made any recent changes on the computer before the issue occurred?

Method 1

Check if both the external drives have drive letter assigned using Disk management.

a)   Open Computer Management by clicking the Start button, clicking  Control Panel, clicking  System and Security, clicking Administrative Tools, and then double-clicking Computer Management. If you're prompted for an administrator password or confirmation, type the password or provide confirmation.

If both the drives does not have an drive letter then try to assign letters and check if it works.

To change, add, or remove a drive letter

a)   Open Computer Management by clicking the Start button, clicking  Control Panel, clicking  System and Security, clicking Administrative Tools, and then double-clicking Computer Management. If you're prompted for an administrator password or confirmation, type the password or provide confirmation.

b)   In the left pane, click Disk Management.

c)    Right-click the drive that you want to change, and then click Change Drive Letter and Paths.

d)   Do one of the following:

                     i.       To assign a drive letter if one has not already been assigned, click Add, click the letter that you want to use, and then click OK.

                    ii.       To change a drive letter, click Change, click  Assign the following drive letter, click the letter that you want to use, and then click OK.

                   iii.       To remove a drive letter, click Remove and then click  Yes to confirm that you want to remove it.

Method 2

If the above step fails then you will need to modify the registry and check.

Important: This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry refer the below link.

Back up the registry

http://windows.microsoft.com/en-US/windows-vista/Back-up-the-registry

a)   Click the Start Button, type "regedit" (without quotation marks) in the Start Search box and then press ENTER.

b)   Navigate to the following key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class{36FC9E60-C465-11CF-8056-444553540000}

c)    Right click the {36FC9E60-C465-11CF-8056-444553540000}entry, choose "Export", select Desktop in the Save in box and type backup in File Name. Click Save.

d)   Please Note: The backup file is on the Desktop and named backup.reg. We can simply restore the registry by double-clicking the backup.reg file.

e)   Highlight this key {36FC9E60-C465-11CF-8056-444553540000}, on the right pane, and then check if Upperfilters and Lowerfilters value are present. If so, please right click on the values and select "Delete" to remove them.

f)    Restart the computer

Reinstall USB controllers

First, please disconnect all USB devices and then perform the following steps:

Using the Keyboard

a)       Click "Start" button, type “devmgmt.msc” (without quotation marks) in the “Search” bar and press "Enter". Click “Continue” if necessary.

b)      In Device Manager, double click to expand "Universal Serial Bus controllers", right click on the Host Controller, click "Uninstall" and click "OK".

c)       Repeat the step 2 to uninstall all items under "Universal Serial Bus controllers".

Then, restart your computer and Windows 7 will reinstall all USB controllers automatically.

Using the Keyboard

First, please disconnect all USB devices. Then, go through the following steps:

1. Press "Ctrl + Esc" to open the “Start” menu.
2. Type “devmgmt.msc” in the Search bar and press "Enter". Click “Continue” if necessary.
3. InDevice Manger, press Tab and use "Up" and "Down" to move the highlight to "Universal Serial Bus Controllers"
4. Press "Right" and expand it.
5. Press "Down" to move to the first item and press "Delete" to remove it.
6. Repeat the step 5 and uninstall all items under "Universal Serial Bus Controllers".

Then, restart your computer and Windows 7 will reinstall all controllers automatically.

Hope this helps!

Halima S   - Microsoft Support.

Visit our  Microsoft Answers Feedback Forum and let us know what you think.

Answer 2

Dear Halima,

Many thanks for your informative response. I applied Method 1 as a solution and it worked - thank you. What puzzles me is that both my external HDD had been assigned letts by Windows 7 but at some point it simply failed to recognise the letters it had allocated. I must admit it caused me to wonder if I had lost my data but it all worked out fine in the end.

Reading this forum I can see others have had similar issues - perhaps this is something Microsoft needs to address.

Once again, thanks for you help.

Africanhudson

Answer 3

Hi AFRICANHUDSON,

Glad to know that you were able to fix the issue and thank you for sharing the information!

Halima S   - Microsoft Support.

Visit our  Microsoft Answers Feedback Forum and let us know what you think.

Answer 4

It's a year later I know, but I found this and tried the first two methods with no luck. Just getting a brand new computer set up and I can't install all my backed up stuff. The external drive shows up in Devices and Printers but not as an available drive in My Computer. Some more ideas would be a help please. This external drive worked fine in my previous two computers.

Thank you very much.