I am also facing the same problem. Whenever try to start apache, it shows this error code
04 AM [Apache] Problem detected!
3:15:04 AM [Apache] Port 80 in use by "Unable to open process" with PID 4!
3:15:04 AM [Apache] Apache WILL NOT start without the configured ports free!
3:15:04 AM [Apache] You need to uninstall/disable/reconfigure the blocking application
3:15:04 AM [Apache] or reconfigure Apache and the Control Panel to listen on a different port
3:15:04 AM [main] Starting Check-Timer
3:15:04 AM [main] Control Panel Ready