How To Fix “Application Is Damaged, Can’t Be Used To Install MacOS” Failure on older Macs

Question

I hope this post will solve the issue if you run into it.

If you trying to install macOS High Sierra / El Capitan on an older like 2010 / 2011 or older. You get the Failure-message mentioned above and if you try to create an macOS-USB-Stick and run the installation from it the message is like “MacOS could not be installed on your computer”.

Please take the Tour as this needs to be a question to be answered. — Allan, Mar 12 '20 at 08:03
Possible duplicate of https://apple.stackexchange.com/questions/299959/failed-to-upgrade-to-os-x-high-sierra-with-two-non-descriptive-errors — lhf, Mar 12 '20 at 09:45

score 1 · Accepted Answer · answered Mar 12 '20 at 07:39

Please check the following, did you redowload the macOS App? So the certificate issue is solved.

If so you should download the macOS App onto a current Mac Model fresh from AppStore and create a macOS-USB-Stick from the newer Mac, this should solve your issue with the AppStore Authentication, so you will be able to run the installation on your older Mac.

score 0 · Answer 2 · answered Mar 12 '20 at 09:14

0

Change the date of the machine to near the date of the installer, say the last day of the year of the installer.

I did that just yesterday to install High Sierra on a 2010 MacBook Pro. I think my installer was 17G65 dated July 2018 and so I changed the date of the machine to December 31, 2018.

answered Mar 12 '20 at 09:14

lhf

7,278

Did not work and the usb-Installation didn’t either. – dhd80 Mar 12 '20 at 09:24

How To Fix “Application Is Damaged, Can’t Be Used To Install MacOS” Failure on older Macs

2 Answers2