If Mailpro refuses to save your message with "iframe or JavaScript detected", it's a security measure. Those elements are not accepted in newsletters.

Why the block? most email clients (Gmail, Outlook, Yahoo) block iframe and JavaScript. They wouldn't work anyway — and they can trigger spam filters.

Most common sources

  • HTML code imported from a web page
  • Code copied from a CMS (WordPress, Wix)
  • Tracking pixels using JavaScript (Analytics, Facebook Pixel…)
  • Embedded videos via iframe (YouTube, Vimeo)

Step-by-step fix

  1. Identify the offending element (review the HTML)
  2. Search for <iframe> and <script> tags
  3. Remove those tags entirely
  4. Replace with clickable images or links
  5. Save again

Use this instead

If you wanted to…Use
Embed a videoThumbnail image + link
Insert a formButton to a landing page
Animate a counterAnimated GIF
Track clicksUTMs (built into Mailpro)

Need help cleaning the HTML? Contact us via the contact form.

Stay focused on what matters. Start free with Mailpro — the editor produces clean, compliant HTML.

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