My server log ( qmail ISOqLog ) say 1.000.000 mail sends in a day. After i examine 1- #@ send ~500.000 messages sended. ( no such user #@ in my system ) 2- email@example.com ~500.000 ( customerdomain not have name1 mail account ) How to find sender ? I try multiple open relay checker. My server not listed in these list , and try open relay. It says this server secured and not open for relay. I think it will be from phpscript ? How to find spammer ?