I've just taken my Sandisk Readycache 32gb away from W7 which will soon have its own ssd and fitted it alongside the WD 80gb which this W 10 build 9879 64 is running on. The driver download has been upgraded and no longer requires the product key. Everything seems to work ok except when reaching the desktop, the User Account Control box opens up. This didn't happen with W7 and I have looked into the U A C settings in vain to stop this happening. The Readycache software is set to start with Windows.