I am running the latest version of Lightroom and am having an issue while working to reorder a ~320 image collection by dragging and dropping individual thumbnails around. After awhile LR will return an error saying
"Cannot reorder photos. Reorder photos by dragging from within grid view not by dragging from another source."
Only trouble is I am dragging from within grid view. As I was for the last 10min or so.
After I dismiss the error, then I can no longer drag thumbnails around. And if I try to go to the Develop for example module, LR freezes and has to be forcibly quit.