I have one of the original Macbooks (2 GHz Intel Core Duo, 758 MB (256 & 512) SDRAM, 60 GB Hard drive) running OS X 10.4.11. I have 26 GB unused in my hard drive. I also have a 250 GB external hard drive connected to it. I work on videos and have been storing them in the external hard drive because they take up so much memory. I have one movie I want to work on but the Mac says I haven't got enough memory left to move the video back into the laptop. The movie is 135 MB. The same thing happened when my son tried to load a game. My kids have been loading a lot of music on the laptop, but I once tried to store this on the external drive but ran into the same problem. Same thing with photos. I've tried to shut everything down using Force Quit, but this isn't solving the problem. Any ideas? Is there something running in the background, and if so what do i do to get at it? Should I upgrade to a larger hard drive or add RAM?