- 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
- 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
- The new drive is not available in Windows
- 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
- You may receive the following error message when you start
The local device name is already in
The new device (or drive) may appear in Device Manager or the
Disk Management console.
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.
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix. Note
If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site: Note
The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
To apply this hotfix, you must have Windows XP Service Pack 2 installed on the computer.
You have to restart the computer after you apply this hotfix.
Hotfix replacement information
This hotfix does not replace any other previously released hotfixes.
The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone
tab in the Date and Time
item in Control Panel.
Windows XP with SP2, x86-based versions
Collapse this tableExpand this table
|File name||File version||File size||Date||Time||Platform||SP requirement||Service branch|
To prevent this issue from occurring, when you map a network
drive, assign the highest available drive letter to the mapped network
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:
- Right-click My Computer, and then click
- Under Computer Management (Local), click
- In the list of drives in the right pane, right-click the
new drive and then click Change Drive Letter and
- Click Change, and in the drop-down box,
select a drive letter for the new drive that is not assigned to a mapped
- Click OK, and then click
Both the mapped network drives and the recently installed drive
appear in Windows Explorer.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
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.
After you install this hotfix, new drives that are attached to the system for the first time are assigned the next available drive letter from all local or mapped network drives. After a drive is attached to the system, the drive uses the same drive letter every time that the drive is reattached even if the drive letter was reused to map a network drive. However, if the drive letter was reused to map a network drive, a conflict with the drive letter occurs. This conflict can cause the drive to be unavailable.
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.