Why i keep getting this error 4013 on my Ipad.

My Ipad suddenly restarted and it is in restore mode. I have tried all the options, different computers, different cables, update itunes and windows. Still the same error. Following process when it gets stuck.

Itunes downloads and extracts the update upon restore

ipad restarts - iTunes status - updating ipad

iPad restarts again - ends with error 4013.