Not got a Win8 machine to hand so I can't give the exact control sequence - but the issue here is that the time server set as the default is broke.

I'll post again when I've got a Win8 machine (unless someone else posts first) but the solution is to set the Internet Time Server, accessible through the Time control panel or via the time in the system tray, and change it to any of the offered time servers EXCEPT the default one.

A right old cockup!