how do i restore my iphone back to orginal settings after its been unlocked

[SMkdesigns]

i have used pwange and winpwn in the past. i need to send my iphone into apple and i need it to look as if were never unlocked. so do i just go into dfu mode and update to the neweest firmware or what do i have to do please help i cannot figure it out and thanks

[rotobadger]

You are correct. Put iPhone into DFU and then restore (to newest firmware if you want). That should do the trick.