Click Upgrade Now and follow the onscreen instructions to begin your upgrade. If you don’t have broadband access, you can upgrade your Mac at any Apple Store. Upgrading from an older version of macOS? If you’re running High Sierra (10.13), Sierra (10.12), or El Capitan (10.11), upgrade to macOS Catalina from the App Store. Upgrade from previous versions to OS X 10.11 (El Capitan) Reinstall El Capitan on a computer already running it. Reinstall while keeping files, applications, and settings; Reinstall while erasing everything on your computer; Upgrade from previous versions to OS X 10.11 (El Capitan) From the Apple menu, select App Store.
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