http://blogs.msdn.com/b/b8/archive/2012/01/16/building-the-next-generat…
"Q) Can I convert data between NTFS and ReFS?
In Windows 8 there is no way to convert data in place. Data can be copied. This was an intentional design decision given the size of data sets that we see today and how impractical it would be to do this conversion in place, in addition to the likely change in architected approach before and after conversion."
A Microsoft viszont tudatosan úgy döntött, hogy nem teszi lehetővé az ilyen jellegű konverziót. Ez van - nekem nem fáj :-)