error al ejecutar xampp

[guadianahidalgo]

hola a todos tengo este error al ejecutar el xampp que puedo hacer

11:54:10 a.m. [main] Initializing Control Panel
11:54:10 a.m. [main] Windows Version: Windows 7 Enterprise SP1 64-bit
11:54:10 a.m. [main] XAMPP Version: 5.6.3
11:54:10 a.m. [main] Control Panel Version: 3.2.1 [ Compiled: May 7th 2013 ]
11:54:10 a.m. [main] Running with Administrator rights - good!
11:54:10 a.m. [main] XAMPP Installation Directory: "c:\xampp\"
11:54:10 a.m. [main] Checking for prerequisites
11:54:11 a.m. [main] All prerequisites found
11:54:11 a.m. [main] Initializing Modules
11:54:11 a.m. [Apache] Problem detected!
11:54:11 a.m. [Apache] Port 80 in use by "Unable to open process" with PID 4!
11:54:11 a.m. [Apache] Apache WILL NOT start without the configured ports free!
11:54:11 a.m. [Apache] You need to uninstall/disable/reconfigure the blocking application
11:54:11 a.m. [Apache] or reconfigure Apache and the Control Panel to listen on a different port
11:54:11 a.m. [mysql] XAMPP MySQL is already running on port 3306
11:54:11 a.m. [main] Enabling autostart for module "Apache"
11:54:11 a.m. [main] Enabling autostart for module "MySQL"
11:54:11 a.m. [main] Starting Check-Timer
11:54:11 a.m. [main] Control Panel Ready
11:54:11 a.m. [Apache] Autostart aborted: Apache is already running
11:54:11 a.m. [mysql] Autostart aborted: MySQL is already running