If you have a removable disk device that is not connected, and you map a share to the drive letter that it uses, when you connect the removable disk, the drive letter may remain mapped to the share, displaying the contents of the shared resource, instead of the removable disk. Alternately, you may find that the drive letter does not appear under Hard Disk Drives in My Computer.
NOTE: A similar problem exists when you map a share to a drive letter used in a disconnect Terminal Services session. When you connect to the session, you may experience the above behavior.
This behavior means that you are unable to access data on the local disk drive.
To workaround this problem, disconnect the mapped network drive.
NOTE: You should NOT map a network resource using the same drive letter as a physical disk that may later be connected.