500 Internal Server Error

I created a user with domain
I uploaded a script
I gave chmod -R 0775 /home/user/public_html/myscript

when i acces domain.com/myscript

he said

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, mail and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

why?

I need acces 775 to work my script

what can i do?

You are using NGINX?

no
i use apache

I have same error when i use cms/script default .htaccess files.

Hello.

You can not using a PHP scripts with eXecutable permission if the script not a CGI.
You have to use next permissions:
755 for a directories; 644 for a .php files.