Email apps and company mail filters change how your emails look. Most differences aren't caused by your template.

Dates, times or addresses turned into colored links

Outlook and some phone mail apps turn dates, times and addresses into tappable links. The template is fine; the recipient's app is styling the text.

Images don't show for some people

The recipient's email security or settings may block images. Ask them to choose "show images" or add your sender to their safe list. Keep important details in text, not only in an image.

Why the same code looks different in each app

Every email app reads HTML and CSS (the code behind an email's layout) in its own way, so code that works in one app can break in another. This matters most if you or a designer edit the HTML in your email template.

• Gmail ignores styles placed in a style block at the top of the email or set by class name. Styles need to be written directly on each element (inline).
• Phone mail apps shrink the email to fit the screen and can turn dates, times and addresses into links.
• Outlook on the web and the new Outlook for Windows handle most modern code much like a web browser.

Classic Outlook for Windows is the hardest

The classic Outlook desktop app for Windows uses Microsoft Word to display emails, not a web browser. Because of that, a lot of common web code doesn't work there:

• Centering with CSS, rounded corners, background images and many spacing settings are ignored or look wrong.
• Layouts built with modern CSS can fall apart. Layouts built with HTML tables hold up best.
• Tables can show borders you didn't add unless each one has its border turned off.
• Fonts that aren't installed on the reader's computer get swapped for a default.

If many of your registrants use classic Outlook, keep the design simple: one column, tables for layout, inline styles and common fonts. Test in classic Outlook before you send. For the specific fixes, see Tips for email templates that look right in Gmail and Outlook

Spacing or fonts look off in one app

Gmail, Outlook and Apple Mail each display HTML a little differently. Test by sending the email to addresses on two or three email apps, including classic Outlook if your audience uses it, before you send it to everyone.

Emails go to spam or fail for one company

If you send from your own domain, the domain needs SPF and DKIM records. Contact Certain Support to request the DKIM records. Support works with our technical team to create them, then sends them to you to add to your DNS. See What to do when registrants do not receive emails - SPF/DKIM/DMARC Failure

Next step: Send a test to yourself on two different email apps and compare.