Mac OS X 10.9 This is a self made 10.9 mavericks full dmg. A file named InstallOS.dmg will download to your Mac.
If you still need macOS Sierra, use this link: Download macOS Sierra. For the strongest security and latest features, find out whether you can upgrade to macOS Catalina, the latest version of the Mac operating system.
The Apple Support Downloads page is most useful for finding software for more recent older Macs, particularly anything that is running a version of Mac OS X, even if it’s no longer a supported or updated system software release, like for Macs running Mac OS X Tiger 10.4 or Mac OS X Snow Leopard 10.6.5.