yes i get this all the time using various operating systems.
there does not seem to be an answer.
it is just trial and error until the thing works.
add to apache2.conf or httpd.conf or wherever
then restart apache2 or the machine.
you may find that apache2 starts working
but still works when you remove the lines you have added
fiddle fiddle fiddle
while this is an old thread it has many visitors so obviously the question remains.