This error is quite common for web developers trying to run a apache server on their computer. We all know what’s the cause of this problem, it’s because the port 80 is in used. Probably because you’ve run some IM that’s using port 80 and one of the most popular is Skype. And now after closing the skype or changing the skype’s port in settings and still can’t run apache, then here’s the step you need.
What we are going to do is to free the port 80 so the apache can run.
All we need to do is to know what’s the PID(Process Identification) so can free the port 80.
After doing the steps above, your apache should now work just like before.