I'm having mixed success with an external hard drive for backups also. It was working just fine for months. Now it sporadically doesn't recognize the external hard drive while everything else in the operating system does recognize the ext. hard drive. I can't backup using manual or automatic. The only solution from tech support is to reinstall N360 which gets tedious.
I have XP v3. I'm wondering if my problem would go away if I could dismantle the 360 backup. I don't plan on extending it after this first year of free back up. Can the 360 backup be turned off?