Trying to update my MacBook Air from Sierra and it says the install is broken.

M_Gibbs wrote:

I get a pop-up that says install upgrade to Mojave but it says the install software is damaged so the upgrade fails. I go to upgrades and it doesn't come up and even do searches in app store. What do I do?

Delete the installer if it is in your applications folder "Install macOS Mojave.app" and empty the trash.

Try again:

https://itunes.apple.com/us/app/macos-mojave/id1398502828?mt=12

olli290 wrote:

says the install software is damaged

I'm having the same problem, deleted the previous Mojave installer and downloaded it again but the message pops up again.

One reason for damaged download is a slow ISP download speed.

You can try a faster Network

You can try a Ethernet cable for a better connection

You can try from SafeBoot mode the download link— a SafeBoot https://support.apple.com/en-us/HT201262

Takes noticeable longer to get to the login screen, does a 5-15 minute disk repair before it fully boots up, and certain system caches get cleared and rebuilt, including dynamic loader cache, etc. Login and try your download again.

I'm having the same problem, deleted the previous Mojave installer and downloaded it again but the message pops up again.