Consider the following scenario. You use the Disk Management snap-in on a computer that is running Microsoft Windows Server 2003, Microsoft Windows XP, or Microsoft Windows 2000 Server. When you do this, the Disk Management snap-in may report that 100 percent of the hard-disk partition that is provided by the original equipment manufacturer (OEM) is available. However, you cannot use the Disk Management snap-in to access the hard-disk partition.
This behavior occurs because the Logical Disk Manager (LDM) service does not mount the file system or assign a drive letter to the hard-disk partition. Therefore, the LDM service does not know the size of the hard-disk partition. Additionally, it cannot access the hard-disk partition. Therefore, the Disk Management snap-in reports that both the size of the hard-disk partition and the amount of available space on the hard-disk partition are the same.