Internal Server Error

Unable to open public/.html

[app/framework/base.php:2152] Base->error()
[app/classes/Page.php:54] Preview->render()
[app/classes/Page.php:14] Page->render()
[app/framework/base.php:1776] Page->getPage()
[app/framework/base.php:1599] Base->call()
[index.php:40] Base->run()