Okay, so this is a weird problem. I have a few external hard drives containing iMovie stuff, iTunes backups, etc. and I wanted to put all their contents onto a single 3TB hard drive. So I select the folders (some of which are hundreds of gigs) and copy and paste them into the big hard drive. Clearly, that will take several hours so I leave the room. When I come back, it looks like its done, but not all the files have copied over. Usually maybe 50-70GB of files are copied over, the rest of the files are "greyed out" and have 0 bytes. But the copying progress bar is gone and it appears its over. I have to end up copying files one by one to ensure they get copied over. Any idea of what the problem is? I Never had such a problem in Snow Leopard before.