The IE=edge meta tag, placed within the <head></head> of your HTML email, enables CSS3 and media query support on Windows Phones, version 7.5 and higher.
This meta tag also enables the “edge” mode in Windows Live Mail and Windows 8 Mail, supporting the use of CSS3 and media queries.
It is important to note that when the IE=edge meta tag is enabled it will create a big in Windows Live Mail breaking images and making the email unprintable in Outlook 2003.
The fix is fairly simple, all that is needed is to include a conditional statement around the IE=edge meta tag, which prevents images from breaking in Windows Live Mail and allows for the email to be printed in Outlook 2003.
<!--[if !mso]><!-- --> <meta http-equiv="X-UA-Compatible" content="IE=edge" /> <!--<![endif]-->