File check.php - What is it and what does it do

The file, file_check.php is a tool used to check SMF source files for common errors like files not beginning with the php opening tag  and not ending with closing tags , it also checks for files saved as UTF-8 BOM.

This tool can be used to diagnose forums with issues such as CAPCTHA verification images not showing, quote problems, etc. Simply upload the file to the Forum's root directory (the same directory as SSI.php), and navigate your browser to:

http://www.example.com/forum/file_check.php