Fortunately, there is a fairly simple solution to the “damaged” installer problem.īelow are the download links for the recent versions of macOS. The cause of this error is an expired certificate, and because the certificate is expired, the “Install macOS” app for Mojave, Sierra, and High Sierra will not run. As first reported by, a fix is quite simple. If you’re getting the above error message when you go to install macOS, you’ll likely experience some panic about what to do. If you are getting an error similar to “This copy of the Install macOS Mojave.app application is damaged, and can’t be used to install macOS”, read on to learn how to fix it. If you have a drive created for Mojave, Sierra, and High Sierra, know that a certificate has expired. I am a big fan of using a tool like DiskMaker X to create them to keep around if I need to wipe a drive and reinstall macOS quickly.
Longtime macOS users will know that even though the Mac has a built-in recovery partition, it’s always useful to have a dedicated USB drive with a macOS installer.
