It seems you do have duplicate objects withing your ""DD Equipment Library Archicad 14 2015" folder.
We can't see the entire list but i am pretty sure they are there somewhere.
Interestingly I deliberately duplicated part of my library.
The library report shows the same as yours - i.e. "Libraries with duplicate objects".
When I select this and press the info button I see a similar report as yours that looks like the library is loaded twice when in fact it isn't.
It is just stating the library that each of the duplicates is in - in this case it is the same one.
The problem is you can list the placed (or all) duplicates and see there names but you can not get the file paths for thes objects.
Archicad needs to give more info.
I thought I would be clever and and look in the object settings dialogue and "Find Library Parts" by searching for the name.
But this only show one instance of the object.
The second is invisible in the object settings dialogue.
You could try deleteing (or better moving) these two objects from your library and re-load.
If there is no duplicate then it will come up as a missing object.
If there is a duplicate then you will be able to see where it is in the object settings dialogue.
Barry.
One of the forum moderators.
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