I would like to comment that I had the same problem on an Fujitsu Lifebook T902; Win8 was not detecting any errors on the ESP file system but after running dosfschk I was finally able to install 12.10.
I would like to comment that I had the same problem on an Fujitsu Lifebook T902; Win8 was not detecting any errors on the ESP file system but after running dosfschk I was finally able to install 12.10.