Why does High Sierra quit all my programs when I lock and close the laptop? After installing High Sierra, whenever I lock and close my MacBook Pro (2015), all my programs have quit once I open it again. Chrome will often show an "unexpectedly closed" message, which seems to indicate that it was not a graceful logout but a sudden forced quit of all programs.

It doesn't happen if I lock the computer and immediately unlock - only, apparently, if I close the laptop and come back after a while (sometimes as little as 5-10 minutes).

Why would this be happening?

High Sierra also freezes for around 5 seconds when I try to Lock the computer before actually locking, which is extremely slow and did not happen in Sierra.

I tried to ask this on Apple forums and got the message: "You are not allowed to create or update this content."

Additional info:
- I'm running latest version of macOS (10.13.1).
- When I unlock the Mac after this kind of mass-crash I often get the Optimizing Your Mac notification
- It just happened to me again after closing the laptop for about 2 minutes
- Twice today, instead of a mass crash, the Mac has just displayed a black screen (though the keyboard lights are on) and I was forced to restart.  (This also happened intermittently with Sierra but not usually 2x in one day.)
While I'm not entirely certain that this is the issue, you could attempt to disable graphics switching on your Mac.

In System Preferences, open the Energy Saver pane. From there, uncheck "Automatic Graphics Switching". To learn more about how to do that, check here: Set graphics performance on MacBook Pro

Note that disabling this setting will cause the discreet graphics to always be on. This may use more energy, but if this resolve the issue it would be helpful to know for troubleshooting.