VAST error codes / NonLinear and companion
VAST error 602: Required companion not displayed
Short answer: A required companion could not be shown, so the ad is dropped.
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
602· Unable to display required Companion.
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
The companion was marked `required` and the player could not render it, which invalidates the whole ad.
Common causes
- `required` companion with no fitting slot
- Required companion resource failed to load
How to fix it
Either provide a slot for the required companion or do not mark it required when the placement cannot guarantee one.
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
- VAST-3.0-companion-required-attr: <CompanionAds> required attribute must be all, any, or none
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