"You don't have permission to save files in the location where screen shots are stored"

Every time I take a screenshot, I get this error:

You don't have permission to save files in the location where screen shots are stored.

How do I fix it?

If you type defaults read com.apple.screencapture location into a Terminal window it should tell you where OSX is currently trying to save screenshots.

You can change the location with a similar command. For example:

defaults write com.apple.screencapture location ~/Desktop will save screenshots to your Desktop.

defaults write com.apple.screencapture location ~/Documents will save screenshots to your Documents folder.

Once you've told it a new location you need to run the following command for OSX to pick up the change.

killall SystemUIServer

Run disk utility and select your hard drive, then repair permissions. While you can do this with apps running it would probably run more smoothly and quickly if you quit out of all open apps before doing this.

If repair permissions fails for whatever reason start the Mac in recovery mode (COMMAND-R upon reboot) and then go into disk utility and repair the disk and then permissions.

If it still fails it may be time for a 3rd-party disk repair utility.