Find the httpd.conf file. In case of Bitnami stack on linux you can find the file in -
"lampstack/apache2/conf/httpd.conf"
In case of XAMPP/LAMP and WAMP you have to find the path of that file and open the file in the text editor. And make the following changes.
Find the following line in entire document -
AllowOverride none
And change this line to -
AllowOverride All
Make sure that there is change in entire document because that line has more than one occurance. Once you do that, restart the server or simple close the server connection and the start again. The changes should take effect immediately.