Hello, I've created an ISO file which I need to back up and keep safe. I have a couple on my macbook pro but due to the large file size, it's taking up alot of space on my hard drive. I tried to drag and drop this onto my external hard drive but when I attempted to move them, it came back with an error message saying it wasn't possible to do due to an error. Can anyone help me figure this out? I can drag and drop every other type of file but for some reason this wont want to work? note: the file itself ranges from 4.9GB - 8GB and I have about 200GB space on my portable hard drive.