it happened to me that the electricity in my building cut out during a software update on my 5300. So it wasn't the phone that turned off, but the pc.
Anyway, when power came back, I was able to repeat the software update process. Maybe you can just try your software update again? Of course, if it doesn't even wanna turn on, that probably won't work... but just try to connect it to PC & to electrical outlet.
.
Message Edited by fred_be9300 on 06-Aug-200711:37 PM
My Nokia history: 5310 (Sep 2008), 5300 (Jan 2007), 6610 (June 2003), 3310 (2001)