Consider the following scenario:

• You try to use an unattended answer file (Unattend.xml) to install Windows Vista.
• To do this, you specify the value of the InstallToAvailablePartition XML element as “true” in the Unattend.xml file.
• The computer does not have an existing system volume. For example, there is no valid active partition on the boot disk.

In this scenario, you may receive the following error message during the installation of Windows Vista:

Windows could not prepare the computer to boot into the next phase of installation.

Note: The InstallToAvailablePartition XML element is in the following section of the Unattend.xml file:
[ImageInstall]\[OSImage]\[InstallToAvailablePartition]