hi all i solved this problem ...I hope it will be helpful......
the backup must be in only one folder!!!! ex: twrp:\backups\myserial\here put the folder with the file in it...not a folder and subfolder
perfect work for me
samsung galaxy next gt-5570
but i used anoter pc (with windows 7) because i can't install keys on my pc (with windows 7)
ERROR NUMER 0x80040706
Description:Object reference not set
Setup will now...