OK - not where I wanted to be - but at least I have a functional MacBook Pro running Yosemite. OK, reinstalled Snow Leopard and tried the Yosemite installer. Once you are in the Safe mode, the next course of action is to get into Disk. When you hold the ‘Shift’ key during startup, your computer will launch into Safe mode Safe mode essentially forces the initiated process to ignore all third party launch daemons and startup items. And, of course, I don't have a functioning Snow Leopard any more. The first thing to try is to get your Mac/MacBook into Safe mode. Downloaded El Capitan installer from the store. I have installers there for everything from Snow Leopard forward. Now I can access Apple Store and my purchase history.

Machine is functioning albeit with a 2010 vintage OS. If I changed the system date and tried to download the installer, I got an immediate error message that would not let me download the installer.Ĭalled Apple support - they referenced all the tricks I had tried then offered that perhaps som 3rd party repair shop might be able to help at some cost.įinally, I happened to have a Snow Leopard DVD. If I downloaded and tried to install, got the 'OS X could not be installed on this computer' error. I tried every trick that everyone has posted herein and NOTHING worked. In fact it was running El Capitan before I erased the disk and tried to do a clean installation using MacOS Recovery. Therefore if your mac came with macOS Sierra, macOS High Sierra, macOS Mojave or macOS Catalina pre installed you will not be able to convert the InstallMacOSX.pkg to the Install OS X El had the same problem with a MacBook Pro 5, 1 late 2008 vintage that is supposed to be able to run El Capitan. Please note you can only convert the InstallMacOSX.pkg to the Install OS X El Capitan.app on a mac that can install El Capitan. Use the Install OS X El Capitan.app to create a new bootable USB installer, How to create a bootable installer for macOS – Apple Support

Install OS X El Capitan.app which will be in your Application folder. When that has downloaded open it and you will get InstallMacOSX.pkg.ĭouble-click on that and an installation window will open, this will convert InstallMacOSX.pkg to the How to upgrade to OS X El Capitan – Apple SupportĪt Section 4 download InstallMacOSX.dmg. The installer should now work, when the installation has finished you can change the Date & Time back to today.Īpple did release updated installer files at the end of October, you can get El Capitan here, One thing you can do as a workaround is to change the Date & Time of the mac to a date in 2018 for example. If you are using an old bootable USB installer you created a while ago then that is the error message you will see.

Recently certificates for older install apps for certain macOS's expired meaning they could no longer be installed.

Mac os list installed packages