SQL Server 2000 Setup requires a drive letter when you use mounted drives

When you install Microsoft SQL Server 2000 when no drive letter is available for assignment to a mounted drive, a dialog box appears in Setup that states that no drive is available. When you click OK, a blank green screen appears and you must manually exit Setup.

SQL Server 2000 Setup requires that the base drive of a mounted drive has an associated drive letter. Setup assigns the next available drive letter to the drive. If all drive letters are already assigned and no drive letter is available, Setup will fail. Setup fails because it requires drive letters for installation. Without an available drive letter, the mounted drive does not appear to be available to SQL Server Setup.

Mounted drives are not currently supported for use with clustered SQL Server installations.
For additional information about SQL Server clustered installations and mounted drives, click the following article number to view the article in the Microsoft Knowledge Base:

To resolve this problem you must make sure that a drive letter is available for all mounted drives on the server where SQL Server is being installed. After the installation is completed, if the drive letter or the drive letters that are currently used or assigned by SQL Server Setup become unavailable, any future attempts to run Setup will fail.

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