Hi, I have an external hard disk drive (LaCie 250GB desktop d2 extreme drive) which I want to use as a backup disk for 2 or more computers. I'll try to explain the question as best as possible. If I connect the drive to computer 1 (mac), add a folder and files to the the drive, then attach the drive to computer 2 (mac), is it possible to prevent computer 2 from accessing the files put there by computer 1. Another words, is there a way that the user on each computer can access/read/write only their own files when the drive is connected to their computer. Each of the computers are networked, but I do not want to mount the drive through the network. I would rather want to connect each computer to the drive individually. Each of the computers run Mac OS X from 10.2 to 10.4.9 (not server). Thank you in advance for a solution to my problem. I have not sure if any third party software is capable of carrying out this function. Cheers.