hi brink and thanks for the reply.
i didnt uninstall norton but managed to use a solution i found while trawling the forums and it worked a treat
basically i updated the intel storage driver using the solution posted in another thread on the forum.
many thanks though for your help and all the excellent tutorials i have used on this site.
fwiw,this seems to be a common problem caused after installing a new hdd.
thanks and regards.