It's on 2.15.50.14. When I turn on data connection, auto, 3g or EDGE... There's only the signal bar...no E, 3g, or H appears. Software 5.51or 5.71 both can't help.
In HSPL, the model is PB81*** HX-BC, ans there is "SECURITY UNLOCKED" written on the top, which is not PB81100 like others without...