VASTlint

VAST error codes / NonLinear and companion

VAST error 600: General CompanionAds error

Short answer: The player could not display a companion ad.

Debug this tag now

If you only have a live URL, test it first. If the failure is in the wrapper chain, inspect each hop. Validate resolved XML when you already have the response.

What your player reported

600 · General CompanionAds error.

Wording from the IAB VAST 4.3 specification error table. Players may shorten or reformat it, but the code is the same.

What it means

A catch-all for companion failures not covered by 601–604.

Common causes

  • No usable companion resource
  • A companion the player cannot place

How to fix it

Check the `<Companion>` resource, dimensions, and required flag. 601–604 are the specific cases.

VAST error codes are runtime buckets emitted by the player. They tell you where the failure happened, not which line of XML caused it. Paste the raw tag into the validator to map this code onto the exact element and rule.

Related vastlint rules

Related error codes

Debug this tag now

Validate the XML, follow the wrapper chain, or check it in CI before launch:

# CLI: exits non-zero on errors, ideal for pipelines
vastlint check creative.xml

Further reading