Lost connection between Kies3 and S4 during Lollipop-upgrade and now I don't know what to do?

[AC Question]

I was trying to upgrade my s4 to lollipop with Kies3 when the connection between the phone and Kies3 was broken. I don't know what happend, but I'm guessing that during the update the phone turned it self off and on again and the pc wouldn't download the USB-driver again or something. Now, Kies3 doesn't recognise the phone and on the phone it just says " Downloading... Do not turn off target!!" Anyone have the faintest idea what to do? I'm completely lost!