I have Windows 10 on my PC and I am using Lightroom 5.7. I have always moved my photo folders inside of Lightroom by left clicking on the folder I want to move that are on my "C" drive and then drag it to my external hard drive and drop it. But today I started getting the message; "There was an error copying the file to the destination you selected. The following files could not be copied:" Then there is a list of all the photos in that folder. If I attempt to do this a second time, I get the message, "That folder already exists at this location." If I open Windows Explorer I can see the folder on the external hard drive, but it is empty. The folder does not appear in Lightroom. I just updated my PC from Windows 7 to Windows 10, but I have used this method for weeks since the upgrade. I have checked permissions on the hard drive folder and everything is allowed. Any help would be greatly appreciated!