Hi Jon and thanks for your reply.
I don't know whether my ISP has had any reply to his email to your technical people. I do know that other TPG users have the same problem with the OPC Dorset site. In reading my ISP's email to your technical people that he copied me, his explanation to them about what he thought the problem was at your end seemed very reasonable.
I remember having the same problem with part of the
Scotland Genealogy website a while back which they eventually resolved.
Thank you very much for your offer to help with any specific information I need, I'll get the details together and send to you.
Regards, Paul