UPDATE: OK, this is what you have to do: Trash the iTunes prefs plist, delete iTunes.app, reinstall iTunes. Works perfectly now. It's been having this problem for about 3 years, and it's finally fixed. What the heck, Apple? ================ Unless I just somehow messed something up, this is a big failure on Apple's part in terms of ease of use. Can someone explain how I back this thing up locally (to my computer)? The buttons are greyed out. I can't press them. Ever since I got my iPhone AND when I had an iPod touch, the backup function has never worked. I have no backups, and it's supposed to back up automatically. It has never done so. It does work if I switch to iCloud backup, but I want a real backup on my own machine. I have 1000GB free on my bootup disk, so that's not the problem. 837MB free on the iPhone. Permissions have been checked, and they're OK. It has never worked in the history of my iPhone.