Login screen on macOS Sierra suddenly with gray background

macos macbook-pro sleep-wake

Solution 1:

When your machine restarts with FileVault enabled, the gray screen login is to unlock FileVault. There are no problems with your machine.

Related

How can I make Intel Core i7 Mac perform at i3 or i5 level?
Upon trying to login to an Active Directory, I am alerted with a window saying the account has expired. How can I enable it?
How do I delete a downloaded iOS software update on iOS 6?
Xcode - Can I develop for iOS 11.1 in El Capitan?
The scanner is in use by application '(null)'
Shutdown Cause: -102
After (exactly) 5-months, my cellular data usage logs reset to zero. What happened?
Why are some characters being replaced with boxed question marks on High Sierra?
Check whether macOS host is affected by serious vulnerability that enables access to the root superuser
Is there any way to update the Bootcamp assistant app?
MBP USB-C charger can't keep up when busy. Is that normal?
MacBook Pro won't boot of freshly installed copy of macOS