failed f16 preupgrade, now stuck in grub2 rescue, can't exit

[jackson byers]

I am now stuck in an unresponsive grub2:  ]
  grub rescue >

it responds to a few commands, such as 'ls'
but in particular it fails on
   exit
which is supposed to quit, instead says
   unknown command 'exit'.

I was attempting a preupgrade from one of my two f14 installs,
both of which worked, prior to this latest problem.
Most of the preupgrade seemed to proceed as expected
but near the end gets pushed to  'grub rescue'.


One difficulty is that my f14 is installed to external usb,
but my bios won't boot from usb, so the boot files have to
be put somewhere on my two internal scsi disks,
which works for me for f14 and  f12, f11 also,
( still working, before this present problem.)


This damaged grub 2  rescue appears to be
only remaining small piece of f16 install:
most of the f16 install  was erased in my frantic attempts
at getting out from this locked-in position.

advice? magic solutions?

Would it help to reinstall my legacy f14 grub to mbr of first internal disk?
Why should this be necessary?
 I did not choose to install f16 bootloader to mbr.
I  am quite sure about this.


I can view the system using an old knoppix cd.

thanks for any advice
Jack