Trouble enabling clean urls

I am having trouble enabling clean URLs in my local Debian 8 server.
mod_rewrite is enabled, pathauto enabled, set allowoverride to all in the section /var/www in apache2 .conf.
Renamed .htaccess in drupal root.
Not using virtual hosts for the moment.
In spite of al my efforts, test for clean URLs fails saying they cannot be enabled.
Please help.

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