"This copy of the Install macOS Mojave app is damaged"

Drifty_Child

macrumors member
Original poster
Dec 12, 2017
62
6
USA
I just received a refurbished MBP 2018 15" right out of the box from Apple, and immediately opened the app store to attempt to install Mojave. However, after the download completed, I clicked Open in the app store, and I get a window saying "This copy of the Install macOS Mojave application is damaged, and can't be used to install macOS."

...What?? This is *literally* the first thing I do upon turning on this computer for the first time ever. How can this have possibly gone wrong? How do I get Mojave on this thing?
 

Absrnd

macrumors 6502a
Apr 15, 2010
579
711
Flatland
You can try a reboot, and try again,
or try a fresh install, but there might be something wrong with the HD, I would take it back.
 

Darth.Titan

macrumors 68030
Oct 31, 2007
2,707
296
Austin, TX
You got a bad download. It happens. That's what checksums are for. Delete the installer from your Applications folder and download again.
 

Drifty_Child

macrumors member
Original poster
Dec 12, 2017
62
6
USA
I tried redownloading it, and was able to open the installer. But now an error occurs whenever I try to install it. It simply says "An error occurred installing macOS". Then I can click "OK", and the installer closes.
 

Crash0veride

macrumors regular
Oct 10, 2016
150
81
Cincinnati
Make sure the date/time is right / updating? Seems unlikely on a new machine, but I've had that message installing on a mac powered off a while and the date wasn't updating.