Hi Marcus,
Thanks for your reply. Your answer sounds logical and well informed. I have heard about some google changes recently but that was regarding Exact Match Domains but if that was all I should be fine.
As a little update. I have asked the developers who fixed the problem exactly what they did; details. Their reply is as follows:
"Regarding Magic SEO Issue
Whenever Magic SEO is installed in .htacess file it is activated from admin; it makes a new cache folder for its functionality.Some one have rename cache file on live server. Magic SEO needs cache folder which is in root directory not in magic SEO folder.So we have reinstalled magic SEO as we want to create a new cache file for its proper working."
You mentioned accessibility of dynamic files. That's interesting. I will take that up with technical support with my hosting provider and also if they know about why the cache file was renamed.
Many thanks again Marcus for your feedback
Pete