리조님이 주신소스로 돌려보았는데요~
(참고로 NT에서 돌려보았습니다)
 Warning: Use of undefined constant toaddr -
assumed 'toaddr' in c:Inetpubwwwroot/send.php3 on line 19
 Warning: Use of undefined constant host -
assumed 'host' in c:Inetpubwwwroot/send.php3 on line 20
 Warning: Use of undefined constant toaddr -
assumed 'toaddr' in c:Inetpubwwwroot/send.php3 on line 37
 Warning: Use of undefined constant host -
assumed 'host' in c:Inetpubwwwroot/send.php3 on line 38
 이런 에러가 나는군요