[CMake] random failures on windows INSTALL target. "file INSTALL cannot copy file"

[Tim St. Clair]

I've been noticing random failures on file copy operations of install
targets when they are copying a lot of files.  (e.g. - headers for a
install library)

    "file INSTALL cannot copy file"

I've verified there is nothing in the way, and I'm uncertain what the
actual error is.
It's intermittent and only happens when copying a large number of files.

Is there a timeout parameter I can set.

-- 
Cheers,
Timothy St. Clair