My friend asked me to jailbreak there iphone, and i said ok, i couldn't download blackra1n for some reason, so i download redsn0w, i did everything it asked me and i got to the boot up screen and it didnt work, can someone please help me if i don't fix there iphone i will have to give them mine 
and i have already tryed to restore it
and i have already tryed to restore it