How can PHP developers effectively troubleshoot and debug issues related to incorrect display of special characters, such as the � symbol, in their scripts?

Special characters like the � symbol often indicate encoding issues in PHP scripts. To solve this problem, developers can set the correct character encoding in their PHP files using the header() function with the Content-Type parameter set to the appropriate charset, such as UTF-8.

header('Content-Type: text/html; charset=UTF-8');