Since this thread seems to be gaining more speed than the other one i'm working on, i figured i'd add these images to help you all out detailing the exact problem.
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I'm having the same issue and I wanted to provide some info specific to my mac, and some info in general to help with diganosis.
First, my specs
Secondly, I am running an aftermarket 500 GB drive.
Third, not sure if this is realated, but this screen suggests the proress will take 3 minutes, then it abruptly umps to the restart phase after about 1.5 - 2.5 minutes.
And finally, here is the seeminly unavoidable error message.
Also, other things I've tried now are
installing it from the "show package contents area",
mounting said DMG and trying to install from there.
installing a package file called "upgradeos.pkg"
no luck.