Good morning, I'm looking for a tool that can handle confirmation emails with captcha and that works with postfix.
The idea is, when somebody sends me an email and this address have never sent me any other mail, automatically the sender receives a message with a web link, explaining that is the first that it sends mail to me and need to authenticate. The link on the message is exclusive to this user, so he clicks on the link and a web page appears and the only thing that he needs to do is put a captcha that was generated and click OK, and the server can accept that mail and all other mails based on this confirmation. Maybe this can be also a time based, so after a while that user needs to do this again. But is so simple, I'm thinking in only a captcha, because the server can follow the message and sender by the generated link. Using a tool like this I can stop all spam mail that arrives my inbox. I'm thinking in using TMDA but only replying a message doesn't seem to be so effective, as this can be handled very easy by a robot. If anyone can help me or knows a tool that can do what I sad, please tell me. Thanks in advance, Gabriel.
