This problem occurs because the Downlevel Timewarp feature is enabled on the file servers. This feature incorrectly returns a "valid directory" response for some incorrectly formatted directory requests.
Note The Downlevel Timewarp feature was developed to support a client that is running Windows 95 or Windows 98.
By default, the registry key is not enabled. However, it is enabled in Windows Small Business Server 2003. Users who have implemented this registry key or who use Small Business Server 2003 together with "Previous Versions" functionality for file shares may be affected.
The registry key can be found at the following location:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\LanmanServer\Parameters
Key Name: DisableDownLevelTimewarp
Type: DWORD
Value: 00000000