Hi to all, Traded in my 4s for a second hand 5 with a "battery issue". Replaced battery and charging port assembly and phone will still only react when plugged in at mains or usb but is stuck in bootloop. It can be discovered in itunes when in DFU, any attempts to restore just lead to error 21. Hours of trawling through forums leads me to believe this can be caused by an infected file from jailbreaking? I think I have exhausted all of the obvious solutions - hard reset, holding volume up etc... I have also tried to access files using iexplorer and ifunbox but neither program will recognize that a device is connected. I have been advised elsewhere to try downloading pangu or evasion and rejailbreaking - I have tried both but to no avail as neither program will find the device connected. Is there something obvious I haven't tried? It's incredibly frustrating. Thanks in advance for any help!