The BFI scanner tasks check for prerequisites such as disk space, catalog presence etc. To check which relevance is returning false, use Task 15: Analyze the Relevance of a Fixlet or Task (10.0.4.0) to create an analysis (select from pull down list in Description tab) and target the servers in question.
As for the SW scan, what error code is returned when it fails? Is the scan timing out?
The catalog download task checks for running scan process. If the scan process is hung as it failed earlier, then the task will not be relevant.
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