Internal Server Error

Invalid argument supplied for foreach()

[app/framework/base.php:2152] Base->error()
[app/classes/File.php:24] Base->{closure}()
[app/classes/Page.php:19] File::getSubPageFile()
[app/framework/base.php:1599] Base->call()
[app/index-app.php:23] Base->run()
[index.php:26] require('/home/gabrol/domains/gabrol.pl/public_html/app/index-app.php')