URL rewrites not working return Apache 404's
Those are the 2 thing you need to ensure are correct.

If .htaccess files are being ignored, you need to check to see that AllowOverride is set correctly. See http://httpd.apache.org/docs/2.4/mod/core.html#allowoverride for details on setting "AllowOverride All". You need to also ensure that it is set in the correct scope - ie, in the right block in your configuration. Be sure you're NOT editing the one in the block, for example.

Third, if you want to ensure that a .htaccess file is in fact being read, put garbage in it. An invalid line, such as "INVALID LINE HERE", in your .htaccess file, will result in a 500 Server Error when you point your browser at the directory containing that file. If it doesn't, then you don't have AllowOverride configured correctly.