Don't do it!
Windows Reddit:
"As another side note, if you see "~Windows ~BT." DO NOT DO NOT DO NOT RUN SETUP.EXE. THINGS MAY BE DELETED AND BAD THINGS MAY HAPPEN [sic]. ESPECIALLY don't run it after everything has been downloaded! I can't tell you how many people in the comments have done this "by accident." Don't run it. Don't run it as administrator. Just don't touch it, don't look at it, leave it well alone. (Hype train broke down. Go directly to /r/britishproblems. Do not pass Go. Do not collect ?200.)"