Sony mp4

I purchase mp4 player and after that i upgrade by Mp3 player upgrade tool and then the mp4 is dead
and mp4 is not on or not detect to the computer please tell me what should i do .
please tell me on to night
its emergency

i bought an 1 GB mp4 player and formatted it . now its only 233 mb. can anybody suggest what to do?? please mail to me rejeesh@keral.com