Email Caster is a marketing tool software that can validate e-mail lists and send customized messages directly to recipients and get instant feedback. It is embedded in SMTP relay, so you do not need to use the SMTP relay server of your ISP. In addition, Email Caster can give you instant feedback on every e-mail sent, after which you can select and delete invalid e-mail addresses from your mailing lists. Email Caster tries to connect with SMTP servers and simulates message sending. It disconnects as soon as the mail server informs whether the address is valid or not without sending the actual message.