Generally you can't change the drive letter as this is given by the OS.
However, you could MAP the drive.
To assign a drive letter to a network computer or folder
1 Open My Computer.
2) On the Tools menu, click Map Network Drive.
3) In Drive, select a drive letter.
4) In Folder, type the server and share name of the computer or folder
you want.
Example:
\\servername\sharename.
-or-
Click Browse to find the computer or folder.
Notes
To open My Computer, click Start, and then click My Computer.
To reconnect to the mapped drive every time you log on, select the
Reconnect at logon check box.
Mapped drives are available only when the host computer is available.
Network drives are assigned letters from Z to A, and local drives (your
hard drive and removable storage devices) are assigned letters from A to
Z.
You can assign a computer or shared folder to a different drive letter
by disconnecting from the drive and then reassigning it to a new drive
letter.
hth
