MacOS – How to permanently disable app relaunch and window restore in Mojave on reboot

If you are looking for a way to permanently disable this feature so you don't have to remember the extra "uncheck the box" step every time you turn your machine off, you can simply deny OS X access to the file it uses to store your session state.

In a terminal,

# Make the file owned by root (otherwise the OS will just replace it)
sudo chown root ~/Library/Preferences/ByHost/com.apple.loginwindow*

# Remove all permissions, so it can't be read or written to
sudo chmod 000 ~/Library/Preferences/ByHost/com.apple.loginwindow*

If you wish to undo this change later and re-enable the feature, perhaps because you've suffered brain damage and now find boot-looping amusing, simply delete this file and the OS will recreate it.

# Re-enable El Capitan's obnoxious "relaunch all the things" behavior
sudo rm -f ~/Library/Preferences/ByHost/com.apple.loginwindow*

There is a simple method for this, for anyone using Lion+.

Navigate to /username/Library

Cannot see Library Folder: While in Finder > Press and Hold OPT key Down > under GO Menu> Select Library

Once there, you will see a folder named Saved Application State

To disable ALL resume states,

1. right-click on Saved Application State > Get info
2. select Locked checkbox

To disable SOME resume states

1. right-click on Saved Application State/Sub-Folder Name > Get info
2. select Locked checkbox

That's it.