Issue
The same email looks different in different email clients, and does not match what is shown in the Email Previewer.
Solution
Different browsers and email clients render HTML and CSS differently. While there are standards set forth by W3C, there is room for flexibility.
At a high level, it is expected for emails to look different, even within the same platform such as Outlook 2013 vs Outlook 2010. With that said, you can code against some of these anomalies by adding extra code in CSS to account for the differences. You should consult with an HTML/CSS designer to make these changes.
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