Post migration issue – punctuation showing as question mark

Hi guys,

I am working for a client who’s site has just been migrated across servers due to hardware issues at the hosting company. Its come back live, but there are some extremely strange things going on.

Most of the punctuation in the body text has been replaced with a question mark icon see here : http://www.mcoe.org.uk/about/

another thing that is very strange (and terrifying) is that when I look at the pages in the editor, they show up as blank. As in, I can see content on the front end, but the back is just a blank text box.

I have no idea what might be causing this, if anyone can point me in the right direction I will be eternally grateful!