iPhone 5s

David Jasper McIntosh

Hi guys, new to the forum. I got an old iphone from one of my friends as the screen on my phone is all cracked. She told me to do a factory reset on it, which i at least tried to do. It gets to about 75% of installing the firmware with itunes, then i get 'an unknown error has occured (-1)'. Has she gavce me a dodgy phone or can it be fixed. Ive tried disabling AV, restarting laptop etc but to no avail. Hoping one of you can help me out here. Much Appreciated if you can