VAST Error 409: Interactive unit not executed
The ad's interactive component (InteractiveCreativeFile, e.g. a SIMID unit) failed to run — the video may have played without its interactive layer.
VAST 4.x separates the video from its interactive layer. Error 409 reports that the player couldn't execute the interactive file — unsupported framework, script error, or a security block — independent of whether the underlying video played.
Players that support the video but not the declared apiFramework fire this while still (usually) playing the plain video.
Why error 409 happens
apiFramework unsupported by the player
A SIMID unit declared where only basic playback exists, or a framework name the player doesn't recognize.
Script errors inside the interactive unit
The interactive file loads but throws at initialization — same class of bug as any broken web app.
CSP or sandbox restrictions
The environment blocks loading or executing third-party scripts in the ad container.
How to fix VAST error 409
- 1
Confirm framework support on the placement
Check what apiFramework values the player actually supports and declare the interactive file accordingly.
- 2
Test the interactive unit in the target environment
Load the interactive file in the placement's real container — console errors there explain most 409s.
- 3
Ensure the video stands alone
Interactive layers should be progressive enhancement; the ad must be complete without them.
Seeing error 409 on a live tag?
Paste the tag URL or XML — the validator resolves the full wrapper chain, validates the schema, downloads every media file, and shows exactly which stage fails.
Validate your VAST tagVAST error 409 — frequently asked questions
Does a 409 mean the impression was lost?+
Not necessarily — many players play the video and report 409 only for the failed interactive layer. Check whether impressions still fired alongside the errors.