same old but weird 403 forbidden error - help!!!

Virtualmin version 3.70.gpl

Everything (FTP - users - mail - directories - permissions - ...) working smooth but not possible to see website, index.html or index.php file, i get always 403 forbidden error?!

The only weird thing that i have found is that there is not a /public_html directory but instead a /public directory where i have put a index.php file and the website in a directory with the name /beeldenstorm

Please help, i am already searching for two weeks on the internet without any solution.

Thanks in advance, i am a Virtualmin beginner :)