VAST Errors

Standardized error codes that indicate where in the delivery chain a video ad failed. A 300-series error points to the wrapper chain, like a redirect that timed out or never returned an ad. A 400-series error means the ad was found but couldn't play. A 900-series error is an undefined or interactive (VPAID) failure. The codes are useful diagnostics. The challenge is that CTV players don't always implement error reporting consistently, so the same failure can produce different codes across publishers. Build a baseline for what error rates look like on clean campaigns, and investigate when you deviate from it.