This common error happens because the security certificates embedded in older installers have expired.
Select your USB drive from the left sidebar and click . mac os sierra 1012dmg download free
But why would anyone want to install an operating system released in 2016 today? The answer often lies in the gentle hum of an older MacBook or iMac—a machine that, while faithful, simply cannot run the latest versions of macOS. For these trusty companions, Sierra is often the final, official, and most stable update they will ever receive, making it the perfect choice to squeeze extra years of secure and functional life out of your hardware. This common error happens because the security certificates
Mac OS Sierra 10.12 is the 13th major release of the macOS operating system, which was announced by Apple on June 5, 2016, at the WWDC 2016. The operating system was released to the public on September 20, 2016. Mac OS Sierra 10.12 is a significant update to the macOS, which brought several new features, improvements, and bug fixes. The answer often lies in the gentle hum
Apple’s older installers use digital certificates that expire over time. If you receive an error stating "This copy of the Install macOS Sierra application is damaged," disconnect your Mac from the internet, open Terminal inside the recovery environment, and change your system clock to 2017 using the command date 0101000017 .
hosts verified community-uploaded images of various macOS versions, including Sierra 10.12. Apple Support Community 2. System Requirements