New Win7 Pro will not recognize USB attached drive

Your USB hard drive needs to:

1) Be shown in Device Management

2) Accessed in Disk Management and either formated or have a drive letter assigned to it

It should also be note that Windows 7 by default will not show "Empty" drives besides the floppy, CD, DVD and internal hard drives.  This is a setting to "deactivate."

Hi alternety599,

a. What’s the make and model of the external hard drive?

You may delete the USB Upper Filter & Lower Filter entry and check if that helps.

Before we go any further, please first backup the Registry.

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, 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/

1.   Click Start, type regedit in the Start search bar and press Enter to open Registry Editor.

2. Locate the UpperFilters value under the following key in the registry:

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

3. On the Edit menu, click Delete, and then click OK.
4. Locate the LowerFilters value under the same key in the registry:

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

5. On the Edit menu, click Delete, and then click OK.
6. Quit Registry Editor and restart the computer.

Hope this helps.