Fix Outlook Button Border Collapsing in Apple Mail (Desktop) — Campaign Monitor Guide for Deliverability & Spam Audits
Spam filters analyze email HTML code quality alongside body copy. Unclosed tags, excessive styling block nesting, and broken link parameters are flagged as spam risks. Below is the targeted integration guide to fix Outlook Button Border Collapsing inside Apple Mail (Desktop) templates when using Campaign Monitor.
Technical Breakdown
Apple Mail (Desktop) uses the WebKit which lacks support for standard rendering rules. This causes Outlook Button Border Collapsing elements to break or collapse when rendering templates.
Campaign Monitor Behaviors
Campaign Monitor wraps custom blocks in dynamic edit tags, which can break the column flow inside Outlook. Ensuring correct class names is essential. Run your finished layouts through the Spam Word Auditor to catch trigger phrases and verify structural delivery alignments before launching.
Remediation Code Block
To guarantee perfectly rounded buttons inside Outlook, we must generate a hybrid VML (Vector Markup Language) roundrect structure overlaid with normal HTML tables. VML is read only by Outlook, while WebKit clients read the HTML layout. In your Campaign Monitor campaign manager, make sure you configure your links to run via [unsubscribe].
<!--[if mso]>
<v:roundrect xmlns:v="urn:schemas-microsoft-com:vml" xmlns:w="urn:schemas-microsoft-com:office:word" href="[unsubscribe]" style="height:44px;v-text-anchor:middle;width:200px;" arcsize="15%" stroke="f" fillcolor="#720e9e">
<w:anchorlock/>
<center style="color:#ffffff;font-family:sans-serif;font-size:13px;font-weight:bold;">Click Here</center>
</v:roundrect>
<![endif]-->
<!--[if !mso]><!-->
<table role="presentation" border="0" cellpadding="0" cellspacing="0" style="border-collapse:collapse;">
<tr><td align="center" bgcolor="#720e9e" style="border-radius:6px;"><a href="[unsubscribe]" style="padding:12px 24px;color:#ffffff;display:inline-block;text-decoration:none;font-weight:bold;">Click Here</a></td></tr>
</table>
<!--<![endif]-->Live Code Sandbox Test
How to Deploy inside Campaign Monitor
Copy the fixed VML or table wrapper code block from the remediation box above.
In Campaign Monitor, click the 'Source' button on your selected editable text region, or edit the template code files directly. Ensure you append the 'class="cs-editable"' flag if you need inline editing later.