• Home
  • /
  • What Outlook in Windows 10 is Doing to Your Email Campaigns

What Outlook in Windows 10 is Doing to Your Email Campaigns

Windows 10 was launched in July of 2015, and with Microsoft offering everyone with a compatible device and the right existing software a limited time free upgrade, a lot of people went ahead and upgraded. Unfortunately ‘free’ is not so free if you consider that the file you’re downloading ranges from 5 to almost 7 GB, that you can’t pause the download and continue at a later stage (which means it has to start from the beginning again!), and that installing the upgrade means any other software you have installed is going to be wiped out!

In any case, what’s done is done and now more than a few of your email subscribers are using Windows 10, along with its built in apps. Microsoft promised that the bugs we all loved to hate about Windows 8 & 8.1 have been eradicated, but unfortunately they weren’t thinking about email marketers so many of the rendering issues that the earlier versions of Outlook are famous for, are still present.

And because those default apps are universal, meaning they’re identical whether you’re using them on a desktop, smartphone or tablet – those rendering issues are present no matter the device your subscriber happens to be using. AND just in case you thought it was going to be simple, there are a few new issues that the ‘universality’ has added to the mix!

Two different rendering engines

Microsoft word is STILL the rendering engine for POP3 & IMAP accounts

For some obscure reason, Microsoft decided to start using Word as the rendering engine for Outlook since they released the 2007 version of their OS. Yes you are reading that right – an email client decided to use a word processing program to render their emails!

Everybody got very excited when it was discovered that the Outlook Mobile and Metro mail apps (Windows Phone 8 and Windows 8 devices respectively) were using Internet Explorer as their rendering engine, and there were hopes that they were finally listening to EVERYONE!

But obviously Microsoft decided that they preferred the rendering capabilities of Word (WHY???), and switched back to it for the default Windows 10 Mail app. So now we are back to trying to get our email campaigns to work in an app that is still stuck almost a decade in the past!

In basic terms what this means that the CSS and HTML support is seriously lacking when compared to other email clients, even after a recent update that improved things. But to be more specific Microsoft Word only supports HTML4, CSS1 and SOME CSS2 specifications.

And this matters – why?

  • Background images, whether in divs or table cells will not display
  • There is no support for divs, so email designers still have to use table based layouts
  • CSS float or position will not work
  • Text shadows don’t work
  • There are issues with padding and margins
  • There are also issues with background colors on nested elements
  • ALT text displays on blocked images, but includes a lengthy security message
  • Most interactive elements don’t work, and HTML forms display as text only
  • Animated GIFs only show the first frame
  • HTML5 videos will not play
  • There is (now) VML support
  • You can (now) use external style sheets


The EAS protocol is used to render emails for Exchange & Office 365 accounts

You would think that every client who uses a ‘universal’ app would have the same experience, however this is NOT the case. Instead anyone using an Exchange or Office 365 account will find their emails rendering with the Exchange ActiveSync protocol rather than the Word engine!

You would think that Word as a rendering engine is terrible but the truth is that while the HTML support is similar, there is even LESS support for CSS techniques. And while you may have seen these problems in other clients, the EAS protocol manages to combine them in one frustrating package!

And this matters – why?

  • There is no support for CSS in your <head>
  • There is no support for web fonts
  • External style sheets are a no go
  • Any VML elements will not work


Other issues causing rendering problems

You can’t differentiate between mobile and desktop

However, because Microsoft has opted for a ‘one Windows for all’ approach and this is a ‘universal’ app, both the desktop version and the mobile version of this app will respond to any mso conditional comments in exactly the same way.

So basically all the issues we love to hate about the desktop versions of Outlook are now present in the mobile version, and then there is the added headache of trying to develop emails that are NOT responsive but still look good on every device.

This version of Outlook also uses Word as its rendering engine, which means that you will be able to use <!–[if mso]> conditional comments, and any other variations that you can think of as well (as long as you’re using the right version number!).

And this matters – why?

Email designers generally use one of two techniques to stop their layouts from going too wide. The first is a max-width layout, and the second is a fixed width layout that is combined with media queries (a CSS3 technique) to make sure it displays properly on smaller mobile devices.

Because Outlook doesn’t support max-width, email designers use a hybrid layout that uses max-width for email clients who DO support it, and a fixed width table that targets desktop clients. Until now Outlook was exclusively a desktop client, so their lack of CSS3 support wasn’t a problem.

But now that there’s no distinction between the mobile and desktop versions and mso conditional comments behave identically for both, your email ALWAYS renders at the fixed width you set – no matter the device it’s being viewed on!


Automatic scaling is not uniform

Understanding PPI and how it effects what you actually see on the screen is difficult, but this article should help. Throw in the fact that Windows 10 automatically scales to meet the needs of a display based on its PPI, but that it has problems with scaling and you start to see the problem.

On top of this is the scaling quirks within Outlook itself. Basically if an element is a VML shape, or uses html attributes to define height and width then Outlook leaves them as pixel or px values. The problem is that Outlook ONLY scales those elements which it has converted to point or pt values.

And this matters – why?

Any elements that retain their px values can ‘break out’ of their tables once the higher PPI scaling is applied because the table will render (appear) smaller but the element with unconverted px values won’t – so that element will not ‘fit’ inside the table anymore.

There is no standard size for a pixel (px) while a point (pt) is equal to EXACTLY 1/72th of an inch, therefore when px values are converted to pt values the proportions of some elements won’t translate well, so text can appear larger and images will scale incorrectly.

These two issues combined mean that some of the elements in your email will end up overlapping each other instead of staying neatly inside the tables where you placed them, and your whole layout can end up looking out of proportion to your original design.


The mobile viewport behaves oddly

Oddly the default viewing state for emails is for them to be zoomed in at 100%, forcing users to zoom out if they actually want to see anything. AND they still have to scroll horizontally because of the reliance on fixed width layouts without the benefit of media queries to adjust them for smaller mobile screens!

Right now it seems that the only way to work around this is to use the hybrid or fluid coding approach, but only use fixed pixel values on the major layout areas (that might cause issues though). Or you could use a more mobile device friendly width, though this means desktop users end up with ‘narrower’ emails.



So far Microsoft has pushed out a number of updates that seem to indicate they are actually listening to the comments, complaints and suggestions they’re getting through their Windows 10 Feedback app, on Windows forums and their app review platforms. But unfortunately Outlook on Windows is still far behind its Android and iOS sister apps, and it is going to require a lot more time and hard work on Microsoft’s part to bring its email rendering capabilities up to par.

Until then email designers, and Outlook users, will just have to grin and bear all the headaches that Outlook delivers – now and in the future! Plus we’ll all be crossing our fingers and hoping for the best, just in case that helps!

About admin Post

admin - Wednesday, 27 July 2016 1:00

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these <abbr title="HyperText Markup Language">HTML</abbr> tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>