Topic: XXWEBPLUS - owl 404 page
page owl 404 for monstra
1) unzip the downloaded file
2) The 404.template.php file do the pasting in public / themes / default (the folder you have your template)
3) login the admin go after content pages and right have the Edit button 404 Page press
4) into the processing 404 page Settings, and select the template 404
that was all!