Apple updated its security certificates in recent years. Older, repackaged .pkg installers from third-party sites often feature expired certificates that El Capitan will reject outright.
If you can't obtain the newer "GarageBand 10" series, the older "GarageBand '11" (version 6.0.5) is an excellent fallback. It is confirmed to work on El Capitan and even on macOS systems up to 10.14 Mojave. Many users prefer the interface and workflow of this version. The Internet Archive is also a great resource for finding this legacy version.
A: You can use the DVD to install GarageBand '11. However, you will likely need to run the GarageBand 6.0.5 updater from Apple (and use the date trick to fix the certificate error) to ensure it runs smoothly on El Capitan. garageband mac os x el capitan 10116 download extra verified
A prompt will appear stating the current version is incompatible, but offering to . For El Capitan, this will typically be GarageBand 10.1.6 . Compatible Versions for El Capitan 10.11.6 Install Old Version of Garageband - Apple Support Community
If GarageBand is not in your purchase history, you cannot officially download an older version. However, you can "force" it into your history using a newer Mac: Apple updated its security certificates in recent years
If you absolutely must use an archive site (like the Internet Archive) because the App Store methods fail, ensure the file hash matches official Apple legacy installers, and scan the downloaded file with an updated version of Malwarebytes for Mac before opening it. System Optimization for GarageBand on El Capitan
Even with a verified download, you may encounter issues: It is confirmed to work on El Capitan
GarageBand for El Capitan 10.11.6 is a robust, free tool for musicians. By finding a verified installer through your "Purchased" history or reputable archives, you can unlock professional-level production capabilities on your legacy Mac.
Because the modern Mac App Store defaults to the newest incompatible version, users on 10.11.6 must use specific methods to acquire a verified, safe copy.