Hi all,
Thanks for the replies and my apologies for the delay in responding.
It turns out the TV was defective as I did everything LG said, but no luck, so returned it to the store, had a new one delivered today and it recognised the hard drive immediately, although it did then say it need to be formatted and asked if it was drive a or b, so i selected a and it then completed the formatting and I was able to access the media on it and play it.
So problem solved; defective TV.