One thing to take note of is how Host Checker determines if your definition is within X updates as it's very different from the 5.X method of checking # of days old: Host Checker, assuming you're pulling the AV Definitions Update every hour or so from Juniper, is given the version # of the past 10 updates for the supported AV's it can check definitions for. This means that when Host checker runs, it grabs the DAT version installed on your computer and compares it to that list of 10. If it's on the list, and within the # you specified, then it'll pass. If it's not on the list, then it fails. This means that if a new DAT is released right now, and you download it before Juniper knows about it, you'll fail the update for not having up to date definitions (Juniper thinks the latest is version 1200, you have version 1201). We used to have this issue a while back, but then we upped the Virus Definition pull to every hour and that mostly went away.
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