Try to factory reset. It will work for sure
Sent from my LG-P920 using xda app-developers app
You seem to fail on flashing CM7 I guess. What you need to do is just downgrade to 2.2.2 stock rom. Search in "General or Development" to find guidance
In Korea, the LG optimus Black has just been upgraded to ICS dude http://www.youtube.com/watch?v=gDrfV0FQPkA
And they say other will be on 25th, Sept and so on !
just 7days left to say goodbye LG