Sometimes on a brand new cPanel install, apache does not want to start and gives the following message.

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root@server [~]# service httpd start
Syntax error on /usr/local/apache/conf/httpd.conf:
UserDir “enable” keyword requires a list of usernames
root@server [~]#
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Usually this happens when Apache mod_userdir Tweak is enabled in WHM before adding any accounts. This creates blank UserDir directives in the httpd.conf file which will not let Apache start.To get around this, simply disable the tweak until the first account is created.

Or you can manually comment the UserDir entries from conf.