After receiving a replacement printer from Xerox and still finding I had the same issue, I have now discovered if I leave the USB cable permanently connected between the printer and my Windows-10 PC after re-installing all Xerox drivers again, neither my wife’s PC nor my PC have any issues printing like was before when they could not wake the printer other than switching its power off & on which rebooted and recycled it. . However we still have this issue with non-wired, Wi-Fi connected devices i.e. phones and iPads. . What I have realised is our broadband supplier ‘BT’ supplies us with a Dynamic Connection (i.e. often changes our ip address) as opposed to other suppliers who don’t; if our address is changed when the Phaser is in sleep mode none of the Wi-Fi connected items can wake the printer unless I power cycle the machine. . I can live with this but thought it might be of interest to others who may have the same old Xerox issue.