Apache – Unable to start httpd on OS X Mavericks

I ran into this problem when I installed apache from source, but then tried to run

$ sudo /etc/init.d/httpd restart 

which was using a pre-installed version of apache. The stop directive in /etc/init.d/httpd was not removing the httpd.pid file that was created when starting the source-installed version of apache.

To determine if this is also the reason for your problem, find where the httpd.pid file is getting set when you run

$ sudo apachectl start

If you installed from source and apache2 is living in /usr/local/apache2, then the httpd.pid file should get created in /usr/local/apache2/logs. When you stop apache by running

$ sudo apachectl stop

this file should get removed. So to test if the httpd.pid file is causing your problem, start apache by calling

$ sudo apachectl start

and locate the httpd.pid file. Then try stopping apache by using

$ sudo /etc/init.d/httpd stop

If the original httpd.pid file is still present, then that is why apache is unable to start when you use

$ sudo /etc/init.d/httpd start

To get my /etc/init.d/httpd file to work correctly, I explicitly put the call to apachectl in the start and stop methods:

#!/bin/bash
# /etc/init.d/httpd
#
# Path to the apachectl script, server binary, and short-form for messages. 
apachectl=/usr/local/apache2/bin/apachectl 
httpd=/usr/local/apache2/bin/httpd 
pid=/usr/local/apache2/logs/httpd.pid 
prog=httpd 
RETVAL=0

start() {
    echo -n $"Starting $prog: "
    $apachectl -k start
    RETVAL=$?
    echo
    return $RETVAL
}
stop() {
    echo -n $"Stopping $prog: "
    $apachectl -k stop
    RETVAL=$?
    echo
}

Worked for me running this command:

fuser -k -n tcp 80