I’m not sure, but it might be that the there is a security filter in the server that blocks access to the file dbconnect.php. After all, this is a file that’s typically used for database connection initialization, in which case there is no legitimate reason why anyone should access it directly.
Could you please try include-ing the file into another PHP script and open that one?
Thanks. I can now use my other php file but i have meet another new problem which is i couldn’t access to my database in order to retrieve my data for my application. I get this error when i try to access to my database on InfinityFree: