ONLINE
Bento

Gmail Image Warnings

Gmail may show "Images in this message are hidden" when it decides images in an email should not load automatically. This can happen because of recipient settings, Gmail testing, machine learning classification, or a safety concern with one of the image domains in the message.

This warning does not always mean your email is spam or that Bento is blocking images. Start by checking the image host, tracking domain, and final linked domains before changing your sending strategy.

What It Means

Gmail normally loads email images through its own image proxy. When Gmail hides images, the recipient may need to click Display images below before they can see logos, product images, or tracking pixels.

The warning can affect:

  • Visible images in the email, such as logos, banners, and product images.
  • The open tracking pixel.
  • Images hosted on your website, CDN, ecommerce platform, or another third-party domain.

If Gmail hides images, opens can be undercounted for that message. Use clicks, replies, conversions, unsubscribes, complaints, and bounces alongside opens while diagnosing the issue.

Common Causes

Common causes include:

  • The recipient has images disabled by default.
  • Gmail is testing or classifying a new sender, domain, template, or image host.
  • The image host domain is new, has little reputation, or was recently used by another sender.
  • The image host or CDN has been flagged by Google Safe Browsing.
  • An image URL redirects through a domain Gmail does not trust.
  • The email uses remote images from an unsafe or unrelated third-party host.
  • The message also contains suspicious links, tracking domains, or redirects.

Gmail's systems are partly automated. A warning may appear during short-lived testing and disappear after Gmail gathers more reputation signals. It can also persist if a host or URL is genuinely flagged.

Avoid hosting email images on random file sharing domains, public URL shorteners, or unrelated third-party domains. Use your own website, your normal CDN, or trusted product image hosts.

Diagnose the Domains

Work through the domains in the full message, not just the sending domain.

  1. Open the email in Gmail.
  2. Choose Show original from the message menu.
  3. Search the source for image URLs, usually img src=.
  4. List every image host domain used in the message.
  5. Check each host in Google Safe Browsing.
  6. Click every link in the email and check the branded tracking domain, final destination, and any redirects.
  7. Confirm your Bento DNS records and link branding are still verified in Deliverability -> DNS Records.

Look closely at:

  • Your logo and header image host.
  • Product image hosts from ecommerce platforms.
  • CDN domains.
  • Custom image URLs added in the email editor.
  • Bento tracking links and your branded tracking domain.
  • Final landing pages linked from buttons and images.

For tracking background, see Open and Click Tracking. For authentication and link branding, see DNS Setup. If Gmail shows a link warning too, follow Gmail Link Warnings.

Wait or Appeal

Wait and monitor if:

  • The warning appears on a new domain, new template, or small test send.
  • Google Safe Browsing shows no issue for the image hosts, tracking domain, and landing pages.
  • Gmail engagement, bounces, complaints, and inbox placement otherwise look normal.
  • The warning appears inconsistently across recipients.

Pause and fix before sending more volume if:

  • Google Safe Browsing flags an image host, tracking domain, or landing page.
  • The warning appears together with a red Gmail suspicious link warning.
  • The affected domain was recently compromised, parked, transferred, or reused.
  • The campaign uses third-party image hosts you do not control.
  • Opens, clicks, replies, and conversions all drop for Gmail at the same time.

Do not solve a flagged image host by only changing the email content. Fix the unsafe or low-trust domain first, then send a small Gmail test before resuming normal volume.

Request a Review

If Google Safe Browsing flags a domain or URL, request a review after fixing the issue:

  1. Go to Google Safe Browsing Report Incorrect Phishing Warning.
  2. Enter the exact image URL, tracking URL, or destination URL that was flagged.
  3. Explain what changed, such as removing a bad image host, cleaning a page, fixing redirects, or verifying the tracking domain.
  4. Submit the request and wait for Google to recheck it.

Reviews are handled by Google, not Bento. If the affected URL is on your own website, also check Google Search Console for security issues.

After the warning clears, send a small test to Gmail before restarting a large campaign. Watch Gmail opens directionally, but rely on clicks, replies, purchases, signups, complaints, and bounces to understand the real impact.