GAM HTML5 ZIP upload errors: what to check and what to send support

Updated October 6, 2026 · Creative Validator

A generic HTML5 bundle error does not identify the failing file or rule. Start by distinguishing an upload rejection from a creative that saves successfully but fails during preview or clicking. Those are different problems and need different evidence.

Check an HTML5 bundle — choose the Google Ad Manager validation profile.

Try the worked examples: Missing primary HTML in a GAM ZIP · A click handler that bypasses clickTag · A missing asset inside an HTML5 ZIP

1. Confirm which archive you are uploading

Extract a delivery folder first if it contains several individual creative ZIPs. Inspect the individual creative archive for an obvious entry document, such as index.html, and its referenced assets. Uploading an outer delivery archive can produce a missing-primary-HTML error or cause an unrelated loose HTML test file to render.

Google's HTML5 guidelines cover the primary document, relative asset references, fixed dimensions and readable click-tag code. Check those requirements against the actual archive rather than just its filename.

2. Check dimensions, weight and exit behavior

Dimensions: declare a fixed width and height with meta name="ad.size" and confirm they match the intended slot.
Weight: Google documents a 1 MB limit for both the bundle and the total extracted files. A small compressed archive can contain much larger files. See Traffic HTML5 creatives.
Clicks: check that the exit uses the configured clickTag value. Search for later assignments that overwrite it with an empty string or bypass it with a different destination.

A literal default URL in a click-tag declaration is not, by itself, proof of a broken exit. Test what happens when the value is changed, then click the creative. Also check the resulting click-tag configuration in GAM after a successful upload.

3. Run a controlled comparison

Keep the original archive unchanged. Give each repair a distinct filename and change one suspected cause at a time. Record whether the original, the repaired version and a minimal control each upload successfully in the same workflow. Confirm the artwork shown in preview belongs to the file you intended to test.

If a minimal control works but the campaign bundle fails, you have narrowed the investigation. You have not yet proved which campaign asset or parser rule caused the rejection.

4. Keep local validation separate from GAM acceptance

A Creative Validator pass means the checks performed did not find a blocking issue. It does not certify Google's private ingestion pipeline. Similarly, rendering in a local browser does not establish that GAM will accept the ZIP. Preserve any remaining uncertainty in the handoff to the creative developer.

When an older creative still serves but the same source archive fails a fresh upload, document both observations. Reusing an existing creative does not exercise the fresh-upload path. Matching source-file hashes can establish that two supplied files are identical, but does not establish that they match GAM's stored asset unless that asset is also retrieved and compared.

5. Give support a reproducible case

The failing individual ZIP, file size and SHA-256 hash; a working control if available.
The network and creative identifiers, upload workflow, exact error text and attempt timestamp with timezone.
The prior successful creative and upload date, if relevant; distinguish upload time from campaign or association dates.
A short original-versus-repaired test matrix with the result of each fresh upload.
The failed upload's response details, if accessible, with credentials removed before sharing.

Ask support to identify the specific processing reason and failing asset, and to provide a correction they have tested through a fresh upload. An HTTP 200 response alone does not prove that the application accepted the bundle; the response body and UI outcome matter.