Xcode breakpoints greyed out and not working

I'm debugging an Objective-C app on the iPhone simulator. The app compiles and works. Xcode settings previously let me set debugger breakpoints and have the debugger actually break.

Now, the breakpoints show up in grey and the debugger doesn't stop on any breakpoint. Clicking on the breakpoint makes it light grey, but not blue like normal.

This screenshot of Xcode shows the greyed out breakpoint.

Can someone tell me which setting I need to revert to enable debugging again? Thanks.

Solution

Open your Debug Area:

enter image description here

Enable the Breakpoint and make it highlighted. BOOM!