Every now and then my Git Tower will stop working “out of the blue” with a message saying something like “Device not configured”.

I found out it actually doesn’t really happen out of the blue. Rather, it happens every time I upgrade Xcode… or when I upgrade Mac OS X altogether.

The real problem is git doesn’t want to work any more as long as you haven’t accepted the new Xcode user license.

To fix this, simply open a terminal and type sudo git. Then follow the instructions and accept the Xcode license.

Then restart Tower and everything should be fine again.