VASTlint

VAST error codes / Wrapper errors

VAST error 300: General wrapper error

Short answer: Something failed while resolving the wrapper chain.

What it means

A catch-all for wrapper resolution problems that are not a timeout (301) or depth limit (302).

Common causes

  • Malformed wrapper that resolves to nothing usable
  • A hop that returns an error document instead of VAST

How to fix it

Walk the chain hop by hop in the inspector. 301 and 303 are the specific cases you usually land on.

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

Use the right tool for this failure

If you already have the resolved XML, run a pure spec check. If you only have a live tag URL, test that endpoint first. If the failure happens in the wrapper chain, inspect each hop.

Validate this XML →Test this live URL →Inspect this wrapper chain →

Further reading