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Unable to install High Sierra - "an error occurred while preparing the installation"

Yes, another thread but a different issue to those already posted. I'm currently running Sierra on a Late 2013 MacBook Pro, on running the High Sierra installer it gets as far as closing down my open applications but then gives the error below:

User uploaded file


The installer log ends with:

Sep 25 21:05:18 MBP osinstallersetupd[9810]: Failed to find contact info

Sep 25 21:05:18 MBP osishelperd[9866]: mountDiskImageWithPath: /macOS Install Data/BaseSystem.dmg

Sep 25 21:05:20 MBP osishelperd[9866]: Couldn't mount base system dmg! (error code 2)

Sep 25 21:05:20 MBP osishelperd[9866]: osishelperd: Failed to mount outer dmg

Sep 25 21:05:20 MBP osinstallersetupd[9810]: Unable to setup bless on disk.

I've rebooted and re-downloaded the installer to no avail, any ideas?

MacBook Pro with Retina display, macOS Sierra (10.12.6)

Posted on Sep 25, 2017 1:25 PM

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Unable to install High Sierra - "an error occurred while preparing the installation"

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