wanna sell my phone. Cant erase content!

[volcom883]

Hey,

I got a 3gs on 4.3.3 baseband 6.15.

When I do a "erase all content and settings" phone always gets stuck! never finished the process.
and when I follow my old guide I cant restore itunes gives me error 21..

guide:
-exit recovery with tiny umbrella
-install normal firmware and cydia with redsnow
-with itunes install custome firmware

Any help would be appreciated

thank you

 

[seanwebb68]

Try putting it into DFU mode then restoring your custom firmware