Failed to upgrade to OS X High Sierra with two non-descriptive errors I've downloaded "Install macOS High Sierra.app" from the Apple App Store. On launching I get:

"This copy of the Install macOS High Sierra.app application is damaged, and can‘t be used to install macOS."

This error can be fixed by following the steps (from https://discussions.apple.com/thread/7675283?start=0&amp;tstart=0):


Go to your applications folder.
Find the installer.
Right click on the installer and click "Show Package Contents".
Click on the folder named "Contents".
Click on the folder named "SharedSupport".
Delete the file named "InstallInfo.plist". 
Enter your administer password to confirm.
Now open the installer.


After deleting InstallInfo.plist, the installer runs. When it gets ready to restart, I get the error message:

"An error occurred while preparing the installation. Try running this application again." (see screenshot)


Searching for this error online suggests it can be linked to a mismatch between the system time and the time server, but my computer has the correct time and is set to update the time automatically.

I am currently running:


OS X El Capitan version 10.11.6. (Note that I was also not able to upgrade to Sierra 10.12, with similar errors)
MacBook Pro (Retina, 13-inch, Early 2015)
Processor 3.1 GHz Intel Core i7
Memory 8 GB 1867 MHz DDR3
I had the same problem with an iMac, 

just delete the update program from your mac and re download it from the App Store. 

If that won't work you should make a Backup with Timemachine and reset your Mac. Try to update again. if it works, recover your data from the backup.

Check this link if you need help with the reset of your system.
https://support.apple.com/kb/PH25649?locale=de_DE&amp;viewlocale=de_DE