You might find that occasionally when you close your MacBook's lid or pick Sleep from the Apple menu on your iMac or Mac mini that it resolutely refuses to go to sleep.
Luckily, it’s not hard to get to the bottom of this problem with your Mac. Ever since OS X Yosemite, you can choose from the View > Column menu when you’re on Activity Monitor’s CPU tab to show a column of processes that are preventing sleep.
Luckily, it’s not hard to get to the bottom of this problem with your Mac. Ever since OS X Yosemite, you can choose from the View > Column menu when you’re on Activity Monitor’s CPU tab to show a column of processes that are preventing sleep.
Click this column header to sort by it and then you can easily find which apps are keeping your Mac awake, then quit them if necessary.