Normal solution for“ XAMPP: Another MySQL daemon is already running” not working

Question

When starting XAMPP, I get the message "XAMPP: Another MySQL daemon is already running.", and MySQL is deactivated in the XAMPP status.

When I try to stop Apache with "sudo /etc/init.d/apache2 stop" I get: "sudo: /etc/init.d/apache2: command not found".

When I try to stop mySQL with "sudo /etc/init.d/mysql stop", I get: "sudo: /etc/init.d/mysql: command not found".

Any thoughts?