I seriously doubt that its the hardware. A good proportion of the logged failures/BSOD`s evaporated when I uninstalled the Norton. More disappeared when I removed a Cloud Back-up client (Livedrive) The remaining problems -including this backup niggle are being experienced by others too you only have to google them and you find people with the same issues. The common denominator is Windows 8 . And I`d rather keep researching the problem until I`ve got a Definitive answer to what is amiss rather than going through all the hassle of returning a machine to the shop then having to re-install EVERYTHING again, especially if it proves to be unneccessary. Besides - if I take it back to the shop They will just say "its a software issue "....then charge me a fortune for support, No thanks... I`ll take it back if I can definitely say its hardware, not until then though. Edit :I`m going to try some third party backup programs next -I`ve been promised an Acronis backup program. its just possible that the new microsoft backup solution "File History" has a bearing on my problem - its one of the only differences I can see between 7 & 8 `s way of backing up. - I did try to use it but it would not recognise the external USB drive although it DID recognise a USB thumb drive (64GB)-which was not big enough.