Warning: main(mainfile.php) [function.main]: failed to open stream: No such file or directory in D:\AppServ\www\sriracha\thungsukla\index.php on line 3

Fatal error: main() [function.require]: Failed opening required 'mainfile.php' (include_path='.;c:\php4\pear') in D:\AppServ\www\sriracha\thungsukla\index.php on line 3