Are you copying the whole file path onto the usb (fullbackup_duo/20120702_1140/vuplus/duo /kernel_cfe_auto.bin and root_cfe_auto.jffs2)
You only need to copy/paste from---- vuplus/duo /kernel_cfe_auto.bin and root_cfe_auto.jffs2 onto the usb ,insert in front panel and reboot,It should then flash no probs .
errrr its so easy when you know what to do...thanks alot that helped!