More details :
I found this command by googling about the problem. It checks if there are any errors in httpd config file
[root@localhost ~]# httpd -t -c httpd.conf
the output was :
Syntax error on line 1 of -c/-C directives:
Invalid command 'httpd.conf', perhaps misspelled or defined by a module not included in the server configuration
I have no idea what that means!
Computers are like air conditioners, they stop working properly if you open Windows.