HTML Email Rendering in Outlook 2007

Traditionally it has been easy for designers to get their HTML email rendered correctly in Outlook, the dominant desktop email client.

Unfortunately this is about to change with the release of Outlook 2007.

Previously Outlook has always utilised Internet Explorer for rendering the HTML but now Microsoft have decided to utilise Word for this purpose.

If anyone has ever used Word to create a HTML you will know how limited its capabilities are.

To see the impact of this on your HTML emails we tested 128 creative’s in Outlook 2007. 28 of these (21.9%) had rendering problems that otherwise would have not existed in previous versions of Outlook.

What HTML does Outlook not support?

On the whole most common HTML tags are supported hence why 100 creative’s rendered perfectly. However background images (background colours are OK) do not get displayed. This is the most widely experienced problem with the tested emails.

In addition the <Margin> tag does not allow you to space your text from the edge of a table cell.

Emails that suffered the main issues were heavily reliant on CSS. While Outlook 2007 supports CSS there are many limitations.

Again the main issue is the lack of support for background images defined by CSS.

Linked CSS style sheets are not supported so make sure you include all CSS within the HTML.

Formatting of bullet points in CSS can cause the bullet points to be forced out of line from each other.

Image dimensions specified by CSS are not applied by Outlook. Therefore we saw on a couple of occasions emails being stretched to the width of the correct image size, not the specified width.

The other common issue is CSS used for positioning being ignored, leaving the email a complete mess.

To help customers overcome these issues we are adding an Outlook 2007 preview in our Inbox Preview feature.

Another useful resource is the Microsoft guide to HTML & CSS rendering in Outlook 2007.

Other issues with Outlook 2007 include:

Phishing – Outlook looks for emails that claim to be from someone but are in fact from a spammer looking to trick you into giving confidential details. Outlook will block the message content including images and links.

Junk Mail Filter – If the Outlook filter catches your email as spam it will block the HTML version, just leaving a stripped plain text version. Another article will focus on the Outlook 2007 spam filter.