Trying to update my wife’s MacBook Pro to Mojave, but every time I download the installer, it tells me it cannot work due to it being “corrupted”. Tried one she had in her download folder and one I recently downloaded from apple, but both gave me the same error. Is this something with Apple’s downloads or do I need to run a surface check or something on her computer? Recently ran Disk Util and it was OK.
First see If an installer says it can’t be verified or was signed with a certificate that has expired.
I don’t know the cause of this either, but it has been going on for months; I tried the download late last year and it did the same thing to me. There was a big discussion then from several experts on line about ways to get around the problem, but none of them seemed to work. I don’t want to go to 64-bit Catalina, and seemingly Apple doesn’t want anyone to go to Mojave, so I’m running High Sierra. Too bad, as Numbers and Pages got an update that doesn’t work below Mojave.
Have you tried this route?
And for those trying to make older system installers you want to read this.
And for real fun and games with Sierra
https://discussions.apple.com/thread/250811969
This last thing you have to read to believe. It comes off as April’s Fool but turns out to be the actual solution.