malformed-interactionsA question result was recorded with no identifier, and most systems drop it.
Question-level reporting is patchy or empty while the overall score records correctly. Item analysis shows fewer questions than the course contains.
A write under cmi.interactions.n.* where that interaction's id was never set.
The id is what an interaction is keyed by. Without it there is nothing to attach the result to, and the usual outcome is that the whole interaction is discarded — quietly, because the score element is unaffected.
Set cmi.interactions.n.id first, before any other field on that interaction, and keep the ids stable across releases so historical reporting still lines up. Ids should be meaningful and unique within the SCO.
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Stuck on this one, or seeing it only in a particular LMS? That is usually a short conversation — scormspecialist.co.uk.