A missing asset inside an HTML5 ZIP

Reviewed October 6, 2026 · Synthetic 160 × 600 example

The broken ZIP includes index.html, which refers to styles.css, but omits that stylesheet. The browser can open the HTML while the creative still lacks a required resource.

Smallest correction

Include styles.css at the relative location used by the HTML. For an incorrectly named or moved resource, correct the reference or restore the file. Compare filename casing as well; a case-insensitive development machine can conceal a mismatch.

<link rel="stylesheet" href="styles.css">

index.html
styles.css  ← must be included at this relative path

The local check covers literal HTML and CSS references. URLs constructed by JavaScript, root-relative hosting paths and external resources need runtime or serving-environment evidence. A clean static result is not a complete network test.

Download and compare

Each link downloads one creative ZIP. Upload that downloaded file directly to the validator; do not wrap it in another ZIP. Extract a copy only to inspect or edit its source.

These examples contain no client assets, vendor scripts or tracking pixels. The corrected banner's click opens Creative Validator's methodology page.

What has been verified

Automated local validation with the GAM profile reports STATIC-MISSING-ASSET for the broken ZIP. The corrected ZIP clears that finding and passes the completed static checks. These examples are generated from fixed source and checked byte-for-byte in the test suite.

GAM upload acceptance is unverified. The examples have not been uploaded to a Google Ad Manager account. A validator pass does not explain an unrelated generic rejection.

Check the destination platform

Upload the corrected individual bundle in the intended account. If accepted, check dimensions, rendering and the configured click destination in the available preview and serving environment. If rejected, preserve the exact error, ZIP and creative identifiers for support.

The GAM API error reference names LINKED_FILES_NOT_FOUND. This is an API classification, not a promise about the wording or cause of a UI error. Also consult Google's HTML5 guidelines.

GAM upload troubleshooting and support evidence

More worked examples

Missing primary HTML in a GAM ZIP · A click handler that bypasses clickTag