Of course you can I do it all the time on 2,3 or 4 computers. I just start a new folder for each computer with the date of back up and what you are backing up. It's great to be able to do several backups of each computer in the even you get hit by a virus, glitches, crashed HD, and in the event you must restore and one copy is compromised, your safe. Never, never, never think that one backup is enough, but rather 2, 3, or 4. Also store one copy somewhere else. You are only limited by the size of your backup HD. You can backup each computer multiple times. Just create a new folder with the computer, data, and date. When it gets full you can just delete the oldest ones and do it again. Remember, don't do it all on just 1 external HD, but rather 2 or 3 of them. You'll never be sorry. Good Luck on you adventures.
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