Whilst trying to copy to disc the PC shutdown. At first I thought it was a one off but now it keeps happening but not all of the time. The PC shutsdown and checks the hard drive for errors, it then starts up again saying that windows has recovered from a serious error. At first it restarted after the first disc check but now it take 2 or 3 attempts. We changed the disc drive but it had no effect. All my anti virus are up to date and I have restored the system to an earlier date but to no avail. I have also run Adware and Spybot.