This has just happened. I've been working on my mac for a bit today, and suddenly I'm not able to navigate through Finder with the tab or arrow keys. Not for than a few minutes ago, I was always able to use tab to go through the icons in the side bar and/or go to the files in a certain folder, and then use the arrows to cycle through the files I wanted, hitting return to open it, etc. Now it won't work. Tab or arrows just go through the folders or files in the current directory, and I have to click on the individual directory in the sidebar to select it. (it won't even highlight 'devices' or places' in the sidebar -- it used to) I haven't touched anything (knowingly, at least). Can anyone give me any advice? I've already restarted the computer, but that hasn't worked and I can't find anything in system preferences or anything like that that would give me a clue. Anyone else have this problem?