vastlint

VAST-2.0-root-element

Root element must be <VAST>

ErrorRequired fieldsIAB VAST 2.0 §2VAST 2.0 and later (all versions)

The top-level element of a VAST document must be named `<VAST>`. Any other root element name — including a byte-order mark, an XML declaration mishap, or a wrapper element like `<response>` — will cause all players to reject the tag entirely.

How to fix

Rename the root element to <VAST>.

Invalid

<VastResponse version="4.0">
  <Ad id="1">…</Ad>
</VastResponse>

Valid

<VAST version="4.0">
  <Ad id="1">…</Ad>
</VAST>
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