My Book Elite Shuts My Computer Down!

Hi, yesterday I installed the above onto my laptop which is running Vista. It appeared to be working ok but seemingly whenever my computer is idle, sometime in that idleness, it shuts down…not properly.

I have tried several times to get my files etc backed up but it was very slow and therefore I couldn’t sit at my laptop waiting for it all night.

Also I have noticed when I re-start my computer by selecting “start windows normally” and go onto the internet, I have to re-login to all my usual sites that usually remember me. So it seems my cookies are being deleted as well when My Book shuts my laptop down???

I have tried another USB port, this made no difference and then I tried My Book on my daughter’s pc which is running XP and what a difference! From setup to backup, it was fast, no problems, I could watch the files being backed up whereas on my laptop the backing up was incredibly slow. What could be wrong here? I cannot easily take the My Book Elite back as I bought it on an auction site (from a legit dealer).

Thanks for any help,