Now I've lost my beloved n900. (The main one)

(I'm using it since some month without USB-port, since it is broken.)

How did I brick my n900?

I've switched to the "Offline-Mode".
At restart my n900 asks if I want to switch to online mode.
But it doesn't react to any answer ...
So it stays always at this dialog and the n900 doesn't start no more.