Hi thanks very much for your time but i am currently building the website and not launched as yet so cannot send you a link. I just want to have a thumbnail and be able to enlarge it when rolled over or magnify i will leave jquery alone as i cannot get to grips with and see if i can do it in dreamweaver a s a moise over effect thanks for your time
Do you have access to a web host? If you're making a website then hopefully you already do. We're not asking to see the final product with all the bells and whistles - just a simple, stripped-down test page with this particular script in so we can try to help you figure out where the problem is. The demo link that John posted works fine but we don't know what's different in your page until we actually see it in full context. Image/script paths could be wrong. You might need to change file name case to work with an Apache server. We don't know how best to help you without all the information upfront and part of that is having access to your live web page.
If I had to guess I would say that the jquery.magnifier.js file is missing. If so, you would have to download it from the demo page or the link below and put it in the same folder as your page: (right click and 'Save As'):
But Beverleyh is right. If you're still having problems, we would need to see a live effort. It doesn't have to be perfect. All it has to do is show what you have so far, like the code in your post would be fine as long as the image(s) and script are on the server.