vista ask for key again

hello,

i have installed windows vista beta 2 on my pc and installation went well,
(at least i think) but now when i start my pc, after a while it asks for my
activation key again because there has been a change in the license or
something, ok fine, so i type in my key again and press next.....but then
after 2 minutes it gives an error called "0x800705B4"


can anyone help me!?