Well try this setup, It just worked in virtual PC2007, gave me option to delete, create, and format [Data] Autopartition=0 UnattendedInstall="Yes" MsDosInitiated=No [unattended] UnattendMode=FullUnattended UnattendSwitch="Yes" OemSkipEula="Yes" FileSystem=* WaitForReboot="No" NoWaitAfterTextMode=1 NoWaitAfterGUIMode=1 DriverSigningPolicy=Ignore NonDriverSigningPolicy=Ignore Hibernation="Yes" OemPreinstall=Yes KeyboardLayout="United Kingdom" the main thing you need is these two. If you prefer to manually choose a partition during text-mode setup with full control on choice of file system, then make sure you have these lines set as they are under the [Data] and [unattended] sections in winnt.sif: [Data] AutoPartition=0 [unattended] FileSystem=*