Strange apostrophe only in IE ’

A friend of mine has written a website for his customer/friend and is having a strange problem.
You can have a look if you want to, the site is www.kenny-baker.co.uk

If he previews it on all browsers on his machine, the site appears as it is supposed to.

Having uploaded it to his customer’s host, the site gives a problem.
In Firefox, Opera and Chrome the site looks fine and as it supposed to do.

Internet Explorer is the problem, and before any of you ask why anyone uses IE anymore, many people do so the site needs to look right on it.
Viewed in IE, every time an apostrophe is used, the apostrophe appears as ’

What should read "Kenny's" appears as "Kenny’s"

Does anyone know why, and what can be done about it?

The problem appears to me to be with the host as the previews are OK, would you agree? This still leaves the problem of a cure.

Can you help?