Q:

PHP readdir() Error 500 Endless Loop

I have a script that works on the server I pay for. However when i try to install the same code under localhost i get this error on an endless loop. 

PHP Warning:  readdir() expects parameter 1 to be resource.

I looked around and some people say that is folder access, but it works on the remote server just not localhost where read and write access is 100%.
Could this be trigger by a setting in php.ini?
I mean other than that, I can't see anything else that will trigger this. 
This is the code where the error points. But I don't think is the code since it works on one server but not the other. Correction I have now loaded this code on hostgator and it works fine also and on my securesignup server. Both work ok. Only localhost is getting this error. 
 $upgraded_folder_path = $CFG['site']['project_path'] . "languages/" . $CFG['lang']['default'] . "/" . strtolower($value) . "/" . $upgraded_folder_name;
            if (!is_dir($upgraded_folder_path) && !($handle = opendir($upgraded_folder_path)))
                {
                while (false !== ($file = readdir($handle)))
                    {
                    if ($file == "." || $file == "..")
                        {
                        continue;
                        }
                    $file_name = $upgraded_folder_path . "/" . $file;
                    if (is_file($file_name))
                        {
                        require_once($file_name);
                        }
                    }
                closedir($handle);
                }

A:

You're calling readdir() only when it's an invalid resource, i.e. - when it failed to open the directory:
 if (!is_dir($upgraded_folder_path) && !($handle = opendir($upgraded_folder_path)))

You can only read an existing directory and one that you can open. If you remove the ! from both of the conditions in that if-statement, it should work fine. Albeit, you also need to make sure the directory exists and your user has permission to read from it.

