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VAST-4.1-tracking-event-value

VAST-4.1-tracking-event-value

Tracking event attribute not in the valid set for this VAST version

ErrorValuesIAB VAST 4.1 §2.4.1VAST 4.1, 4.2, and 4.3

Short answer

The event attribute on <Tracking> must be one of the valid values for the declared VAST version. The finding names the event. When the name was added in a later version, the message names that version: playerExpand and playerCollapse in 4.0, loaded in 4.1, interactiveStart in 4.2.

Why this matters in production

This rule is usually a delivery blocker. Many players, SDKs, and ad servers will discard the response or skip the affected creative once this condition is hit. Value-format rules tend to fail at the moment a player interprets a field such as duration, skipoffset, bitrate, or versioning. They are especially painful because the XML can look valid at a glance. Affected scope: VAST 4.1, 4.2, and 4.3.

How to fix

Replace the invalid event value with one from the allowed set for your declared VAST version — refer to the spec table for your version.

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Other Values rules

VAST-4.1-expires-integer<Expires> value must be an integer number of secondsVAST-4.0-category-authority-not-uri<Category> authority attribute is not a valid authority URLVAST-4.0-category-authority-unknown<Category> authority is not a recognised IAB Content Taxonomy authorityVAST-4.1-blockedadcategories-authority-not-uri<BlockedAdCategories> authority attribute is not a valid authority URLVAST-4.1-blockedadcategories-authority-unknown<BlockedAdCategories> authority is not a recognised IAB Content Taxonomy authorityVAST-4.1-verification-vendor-format<Verification> vendor should use a domain-qualified identifier such as company.com-omidVAST-4.1-verification-tracking-reasonverificationNotExecuted tracking URI should include the [REASON] macroVAST-2.0-duration-format<Duration> value does not match HH:MM:SS[.mmm] format