Change from All Folders to a specific folder for say the first item. There cannot be two files in the same folder as Windows does not allow that. My guess is that the duplicates are in different folders and changing the folder will help you locate the original and the duplicate.
Also open both from the Topic List. Does one have red squares in it? If so you have somehow got an output into to the source.
Post back with what you find.
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@petergrainge
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