How to share drive root of USB hard drive in Windows Server 2008?

Question

Windows Server 2008 -> Computer Management -> System Tools -> Shared Folders -> Shares

I can set up a share for the root of the external drive, but I cannot access it from another computer on the network. On the other hand, if I set up a share for a subfolder on that same drive, I can access it just fine from another computer on the network.

In both cases, the file and share permissions are the same: file system security grants full access to "Everyone", and shared permissions grant full access to "Administrators". The only difference I can see is that access to the share fails when the target folder happens to be the root.

Access behaves differently on the local computer than from another computer on the network...

From the server itself, I can open Explorer and access the default share \\ComputerName\C$ of the main drive, but not the shared root of the external drive \\ComputerName\USBDriveRootShare.

From another computer, I cannot access either. Specifically, if I try to access \\ComputerName\C$ from another computer, I am prompted for a password, but despite providing the correct computer name, username, and password, I am denied access and it just keeps prompting me for the password. If I try to connect to \\ComputerName\USBDriveRootShare, instead of prompting me for a password, it gives me a message "Windows cannot access \\ComputerName\USBDriveRootShare You do not have permission to access \\ComputerName\USBDriveRootShare. Contact your network administrator to request access. That's followed immediately by another dialog that says "\\ComputerName\USBDriveRootShare is currently unavailable."

Answer 1

I found the solution. See: http://support.microsoft.com/kb/947232

Cause:

By default, Windows Vista and newer versions of Windows prevent local accounts from accessing administrative shares through the network.

I know it says "Vista", but Windows Server 2008 seems to be affected by it. By going into my Windows Server 2008 machine and adding a new DWORD registry key "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\LocalAccountTokenFilterPolicy" and setting it to 1, the default administrative share as well as the USB drive root share both become accessible from my Windows 7 machine on the network.

Explanation:

0 = build a filtered token This is the default value. The administrator credentials are removed. These credentials are required for remote administration of the print drivers.

1 = build an elevated token This value enables the remote administration of the print drivers on a server within a workgroup.