VAST error codes / Ad type and trafficking
VAST error 200: Trafficking error
Short answer: The player received an ad type it was not expecting and cannot display.
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
200· Trafficking error. Media player received an Ad type that it was not expecting and/or cannot play.
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 general trafficking mismatch: the creative type returned does not fit the slot the player asked for.
Common causes
- A linear ad served into a non-linear slot, or vice versa
- A creative format the placement was not set up to handle
How to fix it
Check that the creative type returned matches the placement. 201–203 are the more specific versions of this.
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 error codes
- VAST error 201: Expecting different linearity
- VAST error 202: Expecting different duration
- VAST error 203: Expecting different size
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