Content of folders vanished when moved to Macintosh HD I tried to move some folders from my Desktop to my hard drive by dragging them. It would not let me copy them on the hard drive for an unknown reason (red not permitted sign appearing when hovering the external hard drive icon). Then I decided to move all those folders to Macintosh HD by hovering the icon, it looks like everything went great until I started to look into the folders and discover that they were all empty, all folders within folders are still there but every single file vanished!

What should I do ?
Go into Disk Utility, select your hard drive, and then select repair on the right, then select repair disk permissions.

Keep Calm and Repair Disk Permissions