The latest in a line of issues surrounding Microsoft's Surface Pro tablets sees users not being able to turn their devices back on after engaging sleep mode. Some users on the Microsoft Community forum have been complaining that their devices aren't waking up from sleep mode. People are forced to do a hard reboot by holding the power button down for 10 sec to regain access to their machines. Luckily LeoNot has found a fix that's reasonably simple and requires just a simple change to your power management settings. Head over to 'Device Manager' and into 'Network Adapters'. Double press on Marvell Avastar 350N and select the power management tab, then check the box titled "Allow the computer to turn off this device to save power", and your issue should be sorted.