Guest user closes:
Click on Apple in the upper left corner--System Preferences--Users and Groups--The lock in the lower left corner must be opened, then select Guest users, and remove the option to allow guest users to log in to this computer.
Do not display other user login items:
Terminal execution command:
sudo defaults write /Library/Preferences/com.apple.loginwindow SHOWOTHERUSERS_MANAGED -bool FALSE
can be solved.