Try altering that to be on a line that has code on it. (I know we should be able to set breakpoints anywhere, but I am curious). e.g. for (var i:int = 0; i < 100; i++) // set a breakpoint here{ // do not set a breakpoint here // do not set a breakpoint here trace(i); // set a breakpoint here} // do not set a breakpoint here I am wondering if it considers empty lines, braces and other things to be in