[*]What filetype(s) are you trying to sort?
[*]Which windows version do you use?
[*]Are the images in a regular local folder? (not gallery or network)
[*]How many thumbnails are (roughly) shown for this folder?
[*]Were all thumbnails made using the same thumbnailing settings (size, sharpening, etc)?
[*]Were the thumbnails produced using this copy of v9, or imported/converted from an older database?
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[*]Have you tried recreating the thumbnails in that folder?
[*]Have you tried to first select the image that you're most interested in seeing duplicates of, and then resorting the display?
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