How do I save ftp.plist file when using sudo nano? I edited ftp.plist by using sudo nano in terminal, and I saved by control + O but after reboot, it changed again. How can I save the file?
In Finder navigate to /System/Library/LaunchDaemons/ftp.plist


File > Get info Command + i
Tick the "Locked" box


The file should not change now when you reboot.