How can I upgrade from El Capitan to Sierra so that I can install updates on a few legacy applications that won't work beyond macOS 10.12? I have found links to the download page on this site as recent as September, but when I attempt to download the file nothing happens. See https://support.apple.com/en-us/HT208202
Mac Pro, OS X 10.11
Don't use FireFox for this link…
https://itunes.apple.com/us/app/macos-sierra/id1127487414?ls=1&mt=12
Hmmm, maybe caches are remembering bad stuff, but...
Disconnect from the Internet & set the Date back to 2014, then you can run the Install MacsOS Sierra App in Applications, so expired Certificates are not expired.
Thanks again, but I removed the old Sierra upgrade copy from the Applications folder, and then hopefully downloaded another copy. At the end of downloading, the same error message appeared. I went to the Applications folder anyway, and clicked on the icon, but the message appeared again: "This copy of the Install macOS Sierra application is damaged, and can't be used to install macOS" .
You are a wizard! I was a little dubious about those steps, but the process worked very smoothly. Thank you very much for your patient assistance.
Great news, take care my friend! :)
Thanks, but I had already unsuccessfully tried that route (using Chrome). This message appears in the popup window when I attempt a download:
"This copy of the Install macOS Sierra application is damaged, and can't be used to install macOS."
AHA...
If you get a corrupted message...
Naw, not damaged, it's just that you have an old copy already in Applications, Trash the Install MacsOS High Sierra.app in Applications then a new copy more recent version can be downloaded.
Upgrading Mac Pro 5,1 from El Capitan to Sierra
