I installed lampp / xampp on my Ubuntu 12.04. After installing, Apache and MySQL were running properly. Now, they're not. Here's what I get when I try to run apache:
* Starting web server apache2 /usr/sbin/apache2ctl: 87: ulimit: error setting limit (Operation not permitted) (13)Permission denied: make_sock: could not bind to address 0.0.0.0:80 no listening sockets available, shutting down Unable to open logs Action 'start' failed. The Apache error log may have more information.