Not able to see my hard drive in windows explorer?

First Things First, See As Much As You Can

Change the view of My Computer to "Details" and right-click on any column header and click/tick/select to show EVERY column, so that we can see information like size, type, location, etc..

Possible Causes

When looking for attached hard drives, USB flash drives or CD and DVD drives using Windows Explorer, you may notice that some drives are not seen in Windows Explorer or the drive may disappear after a short time or when Windows resumes from Sleep or Hibernation. This can be caused by any of the following:

• Your drive does not have a drive letter assigned to it in Disk Management
• The drive may be disabled or offline
• Your USB driver may be corrupted
• Corrupted registry keys may be causing issues with connecting to your CD or DVD drive

Possible Resolution Methods

1. Run the automated troubleshooter for your version of Windows
2. Make sure that the drive has a drive letter assigned in Disk Management

   Open Administration Tools > Computer Management > Disk Management > File Menu > Action > Rescan Disks and see if then appears. Also, pay close attention to if the drive letter changes in the list of drive in Disk Management.

   If there's no change, try changing the drive letter assignment to something you're sure won't interfere with any drives you've used in the past (permanent, removable, or network) like maybe U: or X: then Rescan Disks and post your results.

3. Make sure that the disk drive is Enabled
4. Make sure that the drive is Online
5. Your USB drive may be corrupted
6. Make sure the drive is recognized and the drivers are working
   1. Plug in and turn on the external USB hard drive
   2. Right mouse click on My Computer
   3. Left click on Manage
   4. Left click on Device Manager
   5. Expand the USB list
   6. Find the USB device for your USB Hard Drive (in my case it was the one that had no description)
   7. Right mouse click - Uninstall
   8. Turn off the external USB hard drive
   9. Turn on the external USB hard drive and let it find and install the driver

7. Corrupted registry keys may be causing issues with connecting to your CD or DVD drive

   Note: To use this method, you must be logged on to Windows as an administrator. If you need help verifying that you are an administrator, go to http://support.microsoft.com/gp/admin

   Important Follow the steps in this section carefully. Serious problems might occur if you modify the registry incorrectly. Before you modify it, back up the registry for restoration in case problems occur.

   This problem may be caused by two Windows registry entries that have become corrupted. To use Registry Editor to delete the corrupted Registry entries, follow these steps:

   1. Press the Windows logo key + R to open the Run dialog box.
   2. Type regedit in the Run dialog box, then press Enter. If you are prompted for an administrator password or for a confirmation, type the password, or click Allow
   3. In the navigation pane, locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class{4D36E965-E325-11CE-BFC1-08002BE10318}

   4. In the right pane, click UpperFilters.

      Note: You may also see an UpperFilters.bak registry entry. You do not have to remove that entry. Click UpperFilters only. If you do not see the UpperFilters registry entry, you still might have to remove the LowerFilters registry entry. To do this, go to step 7.

   5. On the Edit menu, click Delete.
   6. When you are prompted to confirm the deletion, click Yes.

   7. In the right pane, click LowerFilters.

      Note If you do not see the LowerFilters registry entry, go to the next resolution.

   8. On the Edit menu, click Delete.
   9. When you are prompted to confirm the deletion, click Yes.
   10. Exit Registry Editor.
   11. Restart the computer.

8. Additional possible causes:

   • Bitlocker Encryption:

     When an external drive was encrypted with BitLocker (on a Windows 7-based PC) the drive may not be visible when plugging it to another computer (Windows XP-based PC). There may be an expectation of getting a popup asking for the BitLocker encryption key but this does not happen.

     This can be resolved by decrypting and disabling BitLocker while connected to the first Windows 7-based PC, the drive will then be visible as expected on the second PC.

   • Roxio GoBack:

     This problem may occur if you have used the Roxio GoBack program on the hard disk. The problem occurs because Roxio GoBack modifies the master boot record (MBR) and changes the partition type on the hard disk. This can cause the drive to be inaccessible in Windows XP, even when the hard disk appears in Device Manager and in Disk Management console.

     To resolve this problem, contact Symantec for the latest updates to GoBack.

     Or you can work around this problem by using the following steps:

     WARNING: If you are not sure that you can safely follow these steps, contact your hardware documentation or contact the manufacturer of the hard disk or the computer before you continue.

     1. Configure the hard disk as the primary master, and then restart the computer.
     2. Disable Roxio GoBack. To do so, follow these steps:
        1. Press SPACEBAR to view the GoBack boot menu.
        2. Press D to disable GoBack, press Y to confirm, and then press ENTER two times.
     3. Shut down the computer and then return the hard disk to its original configuration.

More info:

• http://support.microsoft.com/kb/330140
• http://support.microsoft.com/kb/314060/en-us
• http://social.technet.microsoft.com/Forums/windows/en-US/dd9cd509-f9ac-4295-a75b-863f92f5595f/windows-7-notices-but-does-not-see-external-usb-hard-drive?forum=w7itprohardware
• Here's a YouTube video that might help too: http://www.youtube.com/watch?v=-siNlFc5QK8