I cannot stress enough the importance of testing your email in several different email clients to check silly like foibles that each one has – it’s easy to miss the below if you only check in a single client.Maplin’s sent this email to me and didn’t realise that if you paste in a trademark TM, it won’t always display properly in some email clients. From what I can gather, it’s some server settings that decide whether it will display properly or not (I’m not too sure on this, don’t quote me on it). What you need to do is replace these reserved characters with their html entity versions – like ™ for TM and © for copyright. For a full list (although I note ™ is missing off it) you can look here: http://www.w3schools.com/tags/ref_entities.asp This is such a silly mistake, and not an email specific related error either. Just rushing and lack of checking in enough email clients.