Trying to install High Sierra on my 2010 iMac currently running Sierra. It downloads the installer then I get a message saying "This copy of the Install macOS High Sierra application is damaged, and can‘t be used to install macOS."?
iMac 27", macOS 10.12
Naw, it's just that you have an old copy already in Applications, there are 2 cures...
Disconnect from the Internet & set the Date back to 2015, then you can run the Install MacsOS High Sierra App in Applications.
Or... trash the App in Applications then a new copy can be downloaded.
Paul Jeffries Said:
"High Sierra download broken?: Trying to install High Sierra on my 2010 iMac currently running Sierra. It downloads the installer then I get a message saying 'This copy of the Install macOS High Sierra application is damaged, and can‘t be used to install macOS.’?"
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Try This: Back up your Mac with Time Machine, and then Install High Sierra using a USB Bootable Installer for High Sierra.
Spot on, thank you. In fact, I slightly suspect you have been snooping around on my mac!
All sorted now, thanks again
LOL, Great news on the fix Paul. :)
Which method did you use?
High Sierra download broken?
