If you're going to nuke your harddisk to install Back track you could try this:
Boot into BT4
[CODE]
fdisk /dev/sda
[CODE]
Then press 'p' to view your partitions, then 'd' followed by the number of the listed partitions when you pressed 'p'. After this press 'w' to save the changes and exit. Reboot and then boot back into BT4 and try and install again.


