[Rd] Rtools install on new Windows 8.1 desktop stalls with "Not responding"

[Dominick Samperi]

Hello,

When I try to install Rtools in the usual way into C:\Rtools on a new
Windows 8.1
desktop it stalls near the beginning of the "Extracting files..." step.

The Task Manager Status for the Setup app shows "Not responding" and it takes
a long time to complete the installation, in spite of the fact that
this is a fast machine
(Intel i7) with 16 GB if RAM.

There were no such stalls when R itself was installed.

Any ideas?

Thanks,
Dominick