I had the exact same problem, I used to have my SIM card without PIN-code, so I turned the PIN back on and restarted the phone -> registering the network = WIN. Dno what is the problem behind this.I can't put any APN in the phone. It doesn't store/save the apn settings when i put it manually in.
Back to B977 and all working but after updated to 2.6.8 its happened againconfirmed
running 2.6.1 with b919 base
imei : unknown
phone number : unknown
no service
sad ... plis help