3900 LTM boots up in grub

After having lost all volumes, an attempt to get the volumes was done. I downloaded a version (11.6.3.3) and installed it from an usb drive. It all went well (no error messages) and after a reboot it only starts up with this:

GNU GRUB  version 0.97  (622K lower / 3930944K upper memory)

[ Minimal BASH-like line editing is supported. For the first word, TAB lists possible command completions. Anywhere else TAB lists the possible completions of a device/filename.]

grub>

Im not so sure where to go from here :( Im still new to the F5 and using this devices in my private small test lab and trying to learn how to setup the load sharing, but then this suddenly happened.

Any help is greatly appreciated, as far as i have seen (using google) its about the boot record that is missing to the new image, but i dont know how to make it boot and where to find it 🙂

Thanks

Kim