I have upgraded to the latest version of Lightroom and all my folders have the dreaded "?" on them. My mac has also upgraded to the new "Photos" (replacing iPhoto), could this have affected Lightroom?
Moving the discussion to Photoshop Lightroom
You seem to have moved the photos and LR can not find them.
Here is how to fix this: http://www.computer-darkroom.com/lr2_find_folder/find-folder.htm
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