CfExecute(TRANSFER_PLACEHOLDERS) returns E_INVALIDARG inside an FSLogix profile container

Your same-server comparison and byte-identical retry succeeding after a directory open make this more specific than a generic invalid-parameter report. They suggest an interaction involving the redirected profile and directory population state, but do not establish a confirmed Microsoft defect or identify which component is responsible. Keep your minimal reproduction and environment matrix as the primary evidence. As a final API-contract check, verify the operation-specific ParamSize, callback connection and transfer identifiers, placeholder counts and completion status against the Cloud Files documentation. Then collect FSLogix support data from both failing and excluded-user runs, preserving matching timestamps and the successful enumeration comparison. Open a Microsoft support case requesting investigation across FSLogix and Cloud Files rather than repeating OS reinstalls. Describe your FILE_LIST_DIRECTORY workaround as an observed mitigation, not a documented requirement. Retain it only with your own regression coverage while seeking an official support determination.