When your Mac boots up, are you bombarded with a series of programs you didn't open and don't regularly use? Startup apps are convenient, but too many can eat up precious memory and slow down your computer. The good news is that you can fight back. Disable Startup Apps The simplest way to disable an app from launching on startup is from the Dock. Right-click on the app and hover over Options in the menu. Apps that are set to open automatically will have a check mark next to Open at Login. Click that option to uncheck it and disable it from opening.