edru on "Page.php template (HTTP ERROR 500 - Theme: Boardwalk)"

Hello,

I'm trying to apply a page template for some pages of my web, for example: portfolio-page.php.

I duplicated the file page.php on my child directory and renamed the file as portfolio-page.php. Then I apply the template in one page but when I try to see it, it appears the HTTP ERROR 500.

I tried deactivating the plugins, creating a new .htaccess and increasing the PHP Memory Limit but no one works.

Any idea of how to fix the problem?
I'm working with the boardwalk theme.

Thanks.