I'm having the exact same problem with an ewin2 pro microsd, i can't upgrade the firmware. I've tried everything!
It also won't boot any roms, just white screens.... hopefully someone can help!?
leo @'d me in a thread about his last dream, stating he was passionately making out with a guy he used to know and then woke up while reaching for his crotch, and said that i would "know who 'tf' it is"
and of course i know, it's luke