Thanks Ray, I have been able to sort this out now.
I still can't see what I did wrong but luckily I had saved a page as a template, with a bit of 'cut and pasting' I used the template to re-create every page.
But I'm still stumped on 2 things which really amount to the same thing.
Included in the code on every page I have the menu plus the footer.
Now originally I had the menu and the footer as a .ssi file in an 'includes' folder. The idea being that if I were to add an extra page to the menu or alter the Copyright year, I'd only have to do it once to the .ssi file instead of amending every page.
For some reason I cannot get this to work now.
If we look at the code I posted earlier we can see:
<!--#include virtual="/includes/menu.ssi" -->
and for the footer
<div id="footer"><!--#include virtual="/includes/footer.ssi" --></div>
So I guess that I have tried to take a short cut somewhere or I just overlooked something.
People who do web design for a living can probably see the obvious, but I did my website in 2009 and really haven't touched it since.
At 62 years old it gets difficult to remember what I did 9 years ago.