How do I fix VAST-4.0-wrapper-root-error?

Remove either all ` ` elements or the ` ` element so only one type exists under ` `.

What does the VAST error " root contains both and elements (invalid per VAST 4.0)" mean?

In VAST 4.0 and later, the ` ` root must contain either ` ` elements **or** a single ` ` element — not both. Mixing them violates the schema choice and may confuse players.

VAST-4.0-wrapper-root-error

<VAST> root contains both <Ad> and <Error> elements (invalid per VAST 4.0)

WarningRequired fieldsIAB VAST 4.0 §2.1VAST 4.0, 4.1, 4.2, and 4.3

In VAST 4.0 and later, the `<VAST>` root must contain either `<Ad>` elements **or** a single `<Error>` element — not both. Mixing them violates the schema choice and may confuse players.

How to fix

Remove either all <Ad> elements or the <Error> element so only one type exists under <VAST>.

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Other Required fields rules

VAST-2.0-root-elementRoot element must be <VAST>VAST-2.0-root-version<VAST> must have a version attribute VAST-2.0-root-version-valueVAST version attribute must be a recognised version string VAST-2.0-root-has-ad-or-error<VAST> must contain at least one <Ad> or <Error>VAST-2.0-ad-has-inline-or-wrapperEach <Ad> must contain exactly one <InLine> or <Wrapper>VAST-2.0-inline-adsystem<InLine> must contain <AdSystem>VAST-2.0-inline-adtitle<InLine> must contain <AdTitle>VAST-2.0-inline-impression<InLine> must contain at least one <Impression>