app/views/layouts/_logo.erb
<!--[if mso]>
<table role="presentation" width="100%">
<tr>
<td style="text-align: center;">
<img src="logo.png" alt="Logo" height="#{height}px" width="auto" style="display: block; margin: 0 auto;">
</td>
</tr>
</table>
<![endif]-->
<!--[if !mso]><!-->
<%= image_tag 'logo.png', height: "#{height}px", width: 'auto' %>
<!--<![endif]-->