Why cant i do the 8.1.2 update through itunes?

[iMore Question]

I have a 5s and allways do the updates through itunes via usb cable. I tried just now 3 times and received each time after a hour of dowload an error report. Just depleted 1.8gig with this!! Why is this?

 

[phreddyl]

are you running the latest version of iTunes? I would delete and reinstall iTunes and try again