New drive or mapped network drive not available in Windows Explorer (297694)


The information in this article applies to:

  • Microsoft Windows XP Home Edition
  • Microsoft Windows XP Professional
  • Microsoft Windows XP Media Center Edition
  • Microsoft Windows XP Tablet PC Edition
This article was previously published under Q297694

SYMPTOMS

When you:
  • create a new volume on a local disk.
  • plug in a removable disk with existing volumes.
  • plug in a removable drive (for example, a USB floppy drive or PCMCIA flash card).
  • add a physical hard disk or CD-ROM drive to your computer.
  • use Offline Files and specify items to be synchronized when you log on.
You may experience any of the following symptoms:
  • An existing mapped network drive is no longer available in Windows Explorer.
  • The new drive is not available in Windows Explorer.
  • The new drive appears in Windows Explorer, but when you open it the contents of the existing drive are displayed.
  • The existing drive appears in Windows Explorer, but when you open it the contents of the new drive are displayed.
  • After your computer starts, the network drive may be replaced by the new drive.
  • After you disconnect the new drive, the mapped network drive letter has the same logical drive letter that it had before you added the new drive.
  • You may receive the following error message when you start your computer:
    The local device name is already in use.
Note The new device (or drive) may appear in Device Manager or the Disk Management console.

CAUSE

This behavior occurs if you map a network drive to the first available drive letter after the drive letters for the local volumes and CD-ROM drives. When you install a new device or volume, Mount Manager, which assigns drive letters to volumes, does not recognize the mapped network drive and assigns the next available drive letter to the new device or volume. This causes a collision with the existing mapped network drive.

WORKAROUND

To prevent this issue from occurring, when you map a network drive, assign the highest available drive letter to the mapped network drive.

To work around this issue if the new volume appears in Disk Management, specify a different drive letter for the new device or volume. To do this, follow these steps:
  1. Right-click My Computer, and then click Manage.
  2. Under Computer Management (Local), click Disk Management.
  3. In the list of drives in the right pane, right-click the new drive and then click Change Drive Letter and Path(s).
  4. Click Change, and in the drop-down box, select a drive letter for the new drive that is not assigned to a mapped network drive.
  5. Click OK, and then click OK again.
Both the mapped network drives and the recently installed drive appear in Windows Explorer.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

MORE INFORMATION

By default, Windows XP assigns mapped network drives to the highest available drive letter, starting with drive Z, to avoid drive letter collisions. However, by default, Windows 2000 assigns mapped network drives to the next available drive letter after the drive letters that are assigned to local volumes and CD-ROM drives.

Offline Files (CSC) synchronization maps a temporary drive to the first available drive letter. If a logon script uses the same drive letter for mapping a network drive, you receive the following error message:
error 85: The local device name is already in use.
Modification Type:MajorLast Reviewed:10/13/2006
Keywords:kbenv kbHardware kbinfo kbnetwork KB297694
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