Well, if you go to the issues section on the left side, it will bring it up so you can find the issue. Sometimes compiling (even though you know it will fail) will bring you straight to the issue. If it is a cryptic runtime error try option clicking the run button, then under the options use resolve addresses, this will shed a little more light, breakpoints are good in these situations.
If you need help with the error, post the error message.
You might also try cleaning the project before re-building it.