Explanation
The Removable Storage service did not detect a valid media library. This could be caused by a transient error in the library when the service queried the removable storage device properties.
User Action
The Removable Storage database can be restored by reinstalling the removable storage device and forcing Windows to rebuild the database.
To restore the database
Right-click My Computer, and then click Manage.
In the left pane, under Computer Management (local), expand System Tools, and then click Device Manager.
In the right pane, expand the device type, right-click the device, and then click Uninstall.
In the left pane, expand Removable Storage, and then expand Libraries.
Under Libraries, right-click the device, and then click Delete.
In the left pane, click Device Manager.
In the right pane, right-click the name of the local computer (usually the first name in the list), and then click Scan for hardware changes.
Restart the computer if you are prompted.
If the driver meets the Plug and Play requirements, a Plug and Play message will be displayed, the device will be automatically installed and configured, and the Removable Storage database will be restored.
參考至:http://www.microsoft.com/technet/support/ee/transform.aspx?ProdName=Windows+Operating+System&ProdVer=5.2&EvtID=15&EvtSrc=Removable+Storage+Service