Skip to main content
sammibennett
Level 2
Jan 21, 2026 1:10 AM UTC
Question

Broken placeholder images - module preview

Hi there, 

We have recently began having issues with the module previews for our email templates not showing the placeholder images. Any ideas on how to fix this/what is causing the issue?

 

 

This post is no longer active and is closed to new replies. Need help? Start a new post to ask your question.

12 replies

SanfordWhiteman
User Group Leader
SanfordWhitemanUser Group Leader
User Group Leader
Jan 21, 2026 2:00 AM UTC

Look in your browser console for protocol errors. Are these placeholders loaded from an http: (not https:) URL?

Translate
sammibennettAuthor
Level 2
Jan 21, 2026 2:18 AM UTC

They’re loaded from an https: 

I have looked in the consol and this is the only thing I could find related to the images loading, could it be a security issue on our company network? (I haven’t tried to replicate the issue off a company device) 
 

 

Translate
Disha_Goyal6
Community Advisor
Disha_Goyal6Community Advisor
Community Advisor
Jan 21, 2026 5:50 AM UTC

​@SanfordWhiteman, I have faced this issue multiple times. Sometimes, there is an issue in email template syntax but other than that I did not find any particular reason for this.

Translate
anildhull
anildhull
Level 2
Jan 22, 2026 3:42 PM UTC

This issue usually occurs when images are loaded from a domain other than your Marketo domain. Please review the email HTML to ensure the correct domain is being used and that the images are not being served from an external domain that does not allow cross-domain requests.

 

Additionally, please confirm whether a new domain was recently added to the instance and whether Marketo’s default domain was used when the email template was originally created. If so, the image URLs in the email template will need to be updated accordingly.

Translate
Anil D
SanfordWhiteman
User Group Leader
SanfordWhitemanUser Group Leader
User Group Leader
Jan 22, 2026 5:55 PM UTC

>  … from an external domain that does not allow cross-domain requests

 

In this case (as you can see in the screenshot) the base images are loaded from Design Studio, which always allows cross-origin requests. It does not have any CORP restrictions.

 

Also, the screenshot functionality is a server-to-server request, which would have no reason to respect CORP restrictions anyway. CORP is a browser thing.  

Translate
Jasbirka
Jasbirka
Level 6
Jan 23, 2026 11:15 AM UTC

Hi ​@sammibennett - Are you using placeholder images from an online editor or a third-party tool? If so, Marketo sometimes doesn't support these images, and they may appear broken. One solution is to upload those placeholders directly to your instance and use them from there.

Please let me know if this resolves your problem.

Translate
SanfordWhiteman
User Group Leader
SanfordWhitemanUser Group Leader
User Group Leader
Jan 23, 2026 5:25 PM UTC

These images are hosted in Design Studio, as noted elsewhere in the thread and shown in the screenshot.

Translate
ss2026
Level 2
Jan 27, 2026 11:44 AM UTC

This usually happens when the placeholder image URL is no longer accessible. Common causes are images hosted on a restricted domain, removed assets, or a switch to HTTPS/CORS restrictions that block Marketo’s preview renderer.

Check that:

  • Placeholder images are hosted in Marketo Design Studio (not external or gated URLs)

  • The image URLs are publicly accessible and not blocked by auth, IP allowlists, or hotlink protection

  • The placeholder isn’t referenced via relative paths or tokens that don’t resolve in preview

Re-uploading the placeholder image to Design Studio and updating the module reference typically fixes this.

Translate
saurabh from miinfotech.com
SanfordWhiteman
User Group Leader
SanfordWhitemanUser Group Leader
User Group Leader
Jan 27, 2026 8:17 PM UTC

 

Translate
    Terms & ConditionsAccessibility statement

    Loading footer...