invalid arch independent ELF magic

[Tim Johnston]

Just installed Ubuntu 11.04 Natty Narwhal. Reboot, and I get:

error: invalid arch independent ELF magic

Then it enters rescue mode.

grub rescue> set

says:

prefix=(md/0)/boot/grub
root=md/0

ls /boot/grub

shows a listing of files, including linux.mod, and so on.

But:

grub rescue> insmod linux

grub rescue> insmod normal

or anything else like that gives the same message: error: invalid arch 
independent ELF magic

I'm not wanting to dual boot, but am wanting to boot off linux software 
RAID (as shown above).

dpgk says that I have

grub-common, grub-efi, and grub-efi-amd installed all at V 
1.99~rc1-13ubuntu3

have tried running grub-install again. It reports no error, but it 
doesn't appear to do anything, problem is still there on reboot.

I wonder why I can't insmod anything. Maybe something incompatible 
between grub version and module version?

Much obliged by any assistance.

regards, Tim Johnston.