usb init error on Arduino uno

Hello. I recently just purchased an Arduino Uno and a usb shield host to unlock ipads. When connecting my uno to either my mac or pc i get the usb init error in serial monitor even when i dont have the usb host connected to the board. Any suggestions or do you think its just a faulty board?

If the last sketch that you loaded caused that error to be shown, removing additional hardware (your USB shield) will not help. The sketch is still in the Uno and if it was printing to the serial monitor it will still do so.

Loading e.g. the blink example and the message should disappear.