my psp 2000 z on 5.50 gen d3, wanted to upgrade to 6.20 pro as some of the games arnt playin on 5.50 (also i dont have a pandora battery).. i have 6.20 pro b6 on psp 3000 n it runs all games.. now, when tryin 2 upgrade to 6.20 from 5.50 gen d3, i get the error that i m currently using some 9.xx version..

now, can sm1 plz tell me how can i upgrade to 6.20..