virtualhost - Apache fails after configuration of 2 virtual hosts

Apache does not restart after having changed the configuration.

Error:
(98)Address already in use: AH00072: make_sock: could not bind to address [::]:80

File: /etc/apache2/sites-enabled/000-default.conf:

Listen 80


    DocumentRoot /var/www/html
    ServerName sladie.myserver.com

    # Other directives here



    DocumentRoot /var/www/html/mydomain.com
    ServerName www.mydomain.com


    # Other directives here

Got this configuration from the Apache Docs.

Any idea why this does not work?

Answer

If you are using Debian, you don't need to specify Listen 80 in your virtualhost, because is declared in

/etc/apache2/ports.conf:9:Listen 80