For starters, the message indicates that you have the ArcFM Structure Relate autoupdater applied to your Dynamic Protective Device feature class for the On Create event and/or the On Update event. (This is normal.) It is therefore trying to locate a 'Structure' feature nearby so it can create the relationship between it and the Dynamic Protective Device. The message is not necessarily an 'error', but rather, informative. So, either 1) there isn't a Structure feature within the search tolerance, or 2) possibly you do not have any feature classes with the 'STRUCTURE' model name assigned. In the first case, it's just letting you know the relationship won't be created (but it will work if there's a 'structure' feature close enough). For the second scenario, you would need to apply the 'STRUCTURE' model name to any pertinent feature classes before it will be able to work properly.
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thank you very much.