I bought this unit with level 4 already installed…what do i do now? I connected serial, set eth1 ip, then rebooted to connect with winbox but the boot message is telling me :
loading kernel from nand …data is corrupted
trying bootp protocol…
and there it sits…
You can format the NAND and reinstall with netinstall
yes, you can do that from within the BIOS Loader menu. License will be safe, so there is no risk.
my choices from the RouteBOOT -2.10
d-boot delay
k-boot key
s-serial console
o-boot device
u-cpu mode
f-try cpu frequency
c-keep cpu frequency
r-reset configuration
e-format nand
g-upgrade firmware
i-board info
p-boot protocol
t-do memory testing
x-exit setup
At the risk of sounding like a complete idiot, which of these options will restore an elf image so I won’t get this message..
addendum: this board doesn’t do this all the time, it will boot properly perhaps 1 out of 10 times on applied power. 
If the device is an RB333 you won’t be the first with this problem.
Well, things going from bad to worse. Reformatted nand.I’m running vista on a laptop and dl’d netinstall, hooked up the Routerboard via ether & serial, ran the netinstall program, and see (in netinstall window)…nothing but my D: drive of the laptop. Googled around for different netinstall version (earlier release) with the same results. Serial com says I’m getting IP assignment to the Routerboard but nothing is getting transferred. 
. Read all the help files, and anything else related to netinstall I could find. Seems I’ve bricked this board with no recourse.Any tips tricks, suggestions…
fixed…some initial problem running netinstall on a vista pc…tried on a XP machine..success!!