My Intrusion Prevention is missing category, class, or event information!

If you find your Intrusion Prevention reports are showing events with missing information in the Category, Classtype, and/or Msg fields:

…there's a pretty quick fix. Go into Apps > Intrusion Prevention > Rules and click the Save button at the bottom right-hand corner. (You don't need to actually make any changes; just click Save immediately.) This forces IPS to regenerate its event map and should populate those fields correctly on future events.