Hello,
I recommend you to check if there are any invalid registry entries related to the USB devices. To do this, follow these steps.
1. Click Start, and then click All Programs.
2. Click Accessories, and then click Run.
3. Type regedit, and then click OK. If you are prompted for an administrator password or for a confirmation, type the password, or click Allow.
4. In the navigation pane, locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class{4D36E965-E325-11CE-BFC1-08002BE10318}
5. 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 8.
6. On the Edit menu, click Delete.
7. When you are prompted to confirm the deletion, click Yes.
8. In the right pane, click LowerFilters.
Note: If you do not see the LowerFilters registry entry, unfortunately this content cannot help you any further.
9. On the Edit menu, click Delete.
10. When you are prompted to confirm the deletion, click Yes.
11. Exit Registry Editor.
12. Restart the computer.
**Important Note:**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, click the following article number to view the article in the Microsoft Knowledge Base:
How to back up and restore the registry in Windows: http://support.microsoft.com/kb/322756
Connect the external hard disk, install the driver and then check for its functionality.
Tips for solving problems with USB devices: http://windowshelp.microsoft.com/Windows/en-US/help/c39bd203-f729-47a4-8351-83291e13c8a81033.mspx
Hope this information is helpful.
All the best!
Thanks and Regards:
Syed V – Microsoft Support.