I have a spare 128 GB/70 GB free Surface Pro and tried installing the WIN 10 Preview 9926 as an in place upgrade. No problem even if it bricks it. Going the Windows Update route, the download and initial install went fine until I got to the usual agreement. After doing that, I got the following helpful message:
“Windows 10 Technical Preview couldn’t be installed.
We’re not sure what happened, but we weren’t able to install the Preview.”
After clearing the failed upgrade from Update and some additional tries, I tried downloading the 64-bit ISO and installing it from a DVD. It ran just long enough to give me a box with the Windows logo. This vanished, and after a few noises from the DVD drive, nothing more happened. I got a fresh ISO on another machine and DVD drive, but no help.
Judging by the silence on the MS support forum, they are as perplexed by the error message as I.
Anybody have a similar problem, and any ideas? I did try booting to Safe mode with network support, but the results are the same with both procedures.